ESA and NASA satellites deliver first joint picture of Greenland Ice Sheet melting

Scientists have delivered the first measurements of Greenland Ice Sheet thickness change using data from ESA and NASA ice satellite missions. With global warming causing the Greenland Ice Sheet to melt and flow more rapidly, raising sea levels and disturbing weather patterns across our planet, precise measurements of its changing shape are of critical importance for tracking and adapting to the effects of climate warming.

ESA and NASA deliver first joint picture of Greenland Ice Sheet melting

Global warming is driving the rapid melting of the Greenland Ice Sheet, contributing to global sea level rise and disrupting weather patterns worldwide. Because of this, precise measurements of its changing shape are of critical importance for adapting to climate change.

Now, scientists have delivered the first measurements of the Greenland Ice Sheet’s changing shape using data from ESA's CryoSat and NASA's ICESat-2 ice missions.

The world's biggest and oldest iceberg is on the move once again

About the size of Rhode Island, the iceberg known as A23a got stuck in an ocean vortex this summer, spinning in place for months. Now, it's free, and heading back into open Antarctic waters.

Temporal stability of a new 40-year daily AVHRR land surface temperature dataset for the pan-Arctic region

Temporal stability of a new 40-year daily AVHRR land surface temperature dataset for the pan-Arctic region Sonia Dupuis, Frank-Michael Göttsche, and Stefan Wunderle The Cryosphere, 18, 6027–6059, https://doi.org/10.5194/tc-18-6027-2024, 2024 The Arctic has experienced pronounced warming the last few decades. This warming threatens ecosystems, vegetation dynamics, snow cover duration, and permafrost. Traditional monitoring methods like stations and climate models lack the detail needed. Land surface temperature (LST) data derived from satellites offer high spatial and temporal coverage, perfect for studying changes in the Arctic. In particular, LST information from AVHRR provides a 40-year record, valuable for analysing trends.

Diversity of novel hydrothermal vent styles on the Arctic ocean floor

A new study about Earth's northernmost seafloor hydrothermal system shows even more variety in vent styles than previously thought. The study has important implications for understanding the origin of these vents and assessing their global-scale impact on the Earth-Ocean system. The study also has implications for understanding and searching for habitable environments, and potentially even life on other ocean worlds in our outer solar system, according to the study's authors. The surprising results found from detailed deep-ocean studies at Polaris call into question how much we really know about the nature of seafloor venting along all ultra-slow spreading ridges on Earth which remain largely unexplored but make up 25% of the global ridge crest.

News at a glance: Mars rover’s big ascent, Europa’s ice sheet, and House committee chairs

The latest in science and policy

Snow depth sensitivity to mean temperature, precipitation, and elevation in the Austrian and Swiss Alps

Snow depth sensitivity to mean temperature, precipitation, and elevation in the Austrian and Swiss Alps Matthew Switanek, Gernot Resch, Andreas Gobiet, Daniel Günther, Christoph Marty, and Wolfgang Schöner The Cryosphere, 18, 6005–6026, https://doi.org/10.5194/tc-18-6005-2024, 2024 Snow depth plays an important role in water resources, mountain tourism, and hazard management across the European Alps. Our study uses station-based historical observations to quantify how changes in temperature and precipitation affect average seasonal snow depth. We find that the relationship between these variables has been surprisingly robust over the last 120 years. This allows us to more accurately estimate how future climate will affect seasonal snow depth in different elevation zones.

Researchers explore, sample and interpret lunar volatiles in polar cold traps

The moon has both a South and North Pole, but just how cold are they? For context, Antarctica's coastal temperatures average around 14°F (-10°C), while the interior drops to -76°F (-60°C), making Earth's South Pole one of the coldest places on the planet. Recent research shows that the South Pole of the moon experiences even more extreme temperature fluctuations and freezing conditions.

Impact assessment of snow thickness, sea ice density and water density in CryoSat-2-derived sea ice thickness

Impact assessment of snow thickness, sea ice density and water density in CryoSat-2-derived sea ice thickness Imke Sievers, Henriette Skourup, and Till A. S. Rasmussen The Cryosphere, 18, 5985–6004, https://doi.org/10.5194/tc-18-5985-2024, 2024 To derive sea ice thickness (SIT) from satellite freeboard (FB) observations, assumptions about snow thickness, snow density, sea ice density and water density are needed. These parameters are impossible to observe alongside FB, so many existing products use empirical values. In this study, modeled values are used instead. The modeled values and otherwise commonly used empirical values are evaluated against in situ observations. In a further analysis, the influence on SIT is quantified.

Distributed surface mass balance of an avalanche-fed glacier

Distributed surface mass balance of an avalanche-fed glacier Marin Kneib, Amaury Dehecq, Adrien Gilbert, Auguste Basset, Evan S. Miles, Guillaume Jouvet, Bruno Jourdain, Etienne Ducasse, Luc Beraud, Antoine Rabatel, Jérémie Mouginot, Guillem Carcanade, Olivier Laarman, Fanny Brun, and Delphine Six The Cryosphere, 18, 5965–5983, https://doi.org/10.5194/tc-18-5965-2024, 2024 Avalanches contribute to increasing the accumulation on mountain glaciers by redistributing snow from surrounding mountains slopes. Here we quantified the contribution of avalanches to the mass balance of Argentière Glacier in the French Alps, by combining satellite and field observations to model the glacier dynamics. We show that the contribution of avalanches locally increases the accumulation by 60–70 % and that accounting for this effect results in less ice loss by the end of the century.

Characterizing ground ice content and origin to better understand the seasonal surface dynamics of the Gruben rock glacier and the adjacent Gruben debris-covered glacier (southern Swiss Alps)

Characterizing ground ice content and origin to better understand the seasonal surface dynamics of the Gruben rock glacier and the adjacent Gruben debris-covered glacier (southern Swiss Alps) Julie Wee, Sebastián Vivero, Tamara Mathys, Coline Mollaret, Christian Hauck, Christophe Lambiel, Jan Beutel, and Wilfried Haeberli The Cryosphere, 18, 5939–5963, https://doi.org/10.5194/tc-18-5939-2024, 2024 This study highlights the importance of a multi-method and multi-disciplinary approach to better understand the influence of the internal structure of the Gruben glacier-forefield-connected rock glacier and adjacent debris-covered glacier on their driving thermo-mechanical processes and associated surface dynamics. We were able to discriminate glacial from periglacial processes as their spatio-temporal patterns of surface dynamics and geophysical signatures are (mostly) different.

Trouble in Arctic town as polar bears and people face warming world

Climate change makes it trickier for Churchill's residents to co-exist with increasingly hungry predators

Polar diatoms fade in the twilight zone

Nature Geoscience, Published online: 18 December 2024; doi:10.1038/s41561-024-01620-0

Sea ice is shrinking during Antarctic winter: here’s what it means for Earth’s oceans and atmosphere

Nature, Published online: 18 December 2024; doi:10.1038/d41586-024-04078-7

Record-low Antarctic sea ice in 2023 increased ocean heat loss and storms

Nature, Published online: 18 December 2024; doi:10.1038/s41586-024-08368-y

Building concrete on Mars from local materials

Imagine you've just gotten to Mars as part of the first contingent of settlers. Your first challenge: build a long-term habitat using local materials. Those might include water from the polar caps mixed with specific surface soils. They might even require some very personal contributions—your blood, sweat, and tears. Using such in situ materials is the challenge a team of Iranian engineers studied in a research project looking at local materials on Mars.

Anti-whaling activist Paul Watson released from jail in Greenland

Danish authorities reject a Japanese bid to extradite the campaigner because of his time spent in detention.

Refining lake volume estimation and critical depth identification for enhanced glacial lake outburst flood (GLOF) event anticipation

Refining lake volume estimation and critical depth identification for enhanced glacial lake outburst flood (GLOF) event anticipation Nazir Ahmed Bazai, Paul A. Carling, Peng Cui, Wang Hao, Zhang Guotao, Liu Dingzhu, and Javed Hassan The Cryosphere, 18, 5921–5938, https://doi.org/10.5194/tc-18-5921-2024, 2024 We explored the growing threat of glacier lake outburst floods (GLOFs) driven by glacier surges in the Karakoram. Using advanced remote sensing and field data, we identified key lake volumes and depths that indicate potential GLOFs. Our findings improve early warning systems by providing rapid methods to assess lake volumes in remote areas. This research seeks to protect vulnerable communities and contribute to global efforts in predicting and mitigating catastrophic flood risks.

Brief communication: Accurate and autonomous snow water equivalent measurements using a cosmic ray sensor on a Himalayan glacier

Brief communication: Accurate and autonomous snow water equivalent measurements using a cosmic ray sensor on a Himalayan glacier Navaraj Pokhrel, Patrick Wagnon, Fanny Brun, Arbindra Khadka, Tom Matthews, Audrey Goutard, Dibas Shrestha, Baker Perry, and Marion Réveillet The Cryosphere, 18, 5913–5920, https://doi.org/10.5194/tc-18-5913-2024, 2024 We studied snow processes in the accumulation area of Mera Glacier (central Himalaya, Nepal) by deploying a cosmic ray counting sensor that allows one to track the evolution of snow water equivalent. We suspect significant surface melting, water percolation, and refreezing within the snowpack, which might be missed by traditional mass balance surveys.

New study says we're unlikely to find liquid water on Mars anytime soon

More than a hundred years ago, astronomer Percival Lowell made the case for the existence of canals on Mars designed to redistribute water from the Martian ice caps to its lower, drier latitudes. This necessarily meant the existence of Martians to build the canals.

A fast and simplified subglacial hydrological model for the Antarctic Ice Sheet and outlet glaciers

A fast and simplified subglacial hydrological model for the Antarctic Ice Sheet and outlet glaciers Elise Kazmierczak, Thomas Gregov, Violaine Coulon, and Frank Pattyn The Cryosphere, 18, 5887–5911, https://doi.org/10.5194/tc-18-5887-2024, 2024 We introduce a new fast model for water flow beneath the ice sheet capable of handling various hydrological and bed conditions in a unified way. Applying this model to Thwaites Glacier, we show that accounting for this water flow in ice sheet model projections has the potential to greatly increase the contribution to future sea level rise.  We also demonstrate that the sensitivity of the ice sheet in response to external changes depends on the efficiency of the drainage and the bed type.

I track changes in the Arctic Ocean to help manage its future

Nature, Published online: 16 December 2024; doi:10.1038/d41586-024-04120-8

World's biggest iceberg heads north after escaping vortex

The world's biggest iceberg is drifting towards the Atlantic Ocean after being stuck near Antarctica.

Buried landforms reveal North Sea's ancient glacial past

Glaciologists used sound waves to reveal Ice Age landforms buried beneath almost 1 km of mud in the North Sea. The results suggest that the landforms were produced about 1 million years ago, when an ice sheet centered over Norway extended towards the British Isles.

Earth from Space: Jakobshavn Glacier, Greenland

Image: These summer images from the Copernicus Sentinel-2 and Sentinel-1 missions showcase different satellite views of Greenland’s west coast.

Future permafrost degradation under climate change in a headwater catchment of central Siberia: quantitative assessment with a mechanistic modelling approach

Future permafrost degradation under climate change in a headwater catchment of central Siberia: quantitative assessment with a mechanistic modelling approach Thibault Xavier, Laurent Orgogozo, Anatoly S. Prokushkin, Esteban Alonso-González, Simon Gascoin, and Oleg S. Pokrovsky The Cryosphere, 18, 5865–5885, https://doi.org/10.5194/tc-18-5865-2024, 2024 Permafrost (permanently frozen soil at depth) is thawing as a result of climate change. However, estimating its future degradation is particularly challenging due to the complex multi-physical processes involved. In this work, we designed and ran numerical simulations for months on a supercomputer to quantify the impact of climate change in a forested valley of central Siberia. There, climate change could increase the thickness of the seasonally thawed soil layer in summer by up to 65 % by 2100.

Projections of precipitation and temperatures in Greenland and the impact of spatially uniform anomalies on the evolution of the ice sheet

Projections of precipitation and temperatures in Greenland and the impact of spatially uniform anomalies on the evolution of the ice sheet Nils Bochow, Anna Poltronieri, and Niklas Boers The Cryosphere, 18, 5825–5863, https://doi.org/10.5194/tc-18-5825-2024, 2024 Using the latest climate models, we update the understanding of how the Greenland ice sheet responds to climate changes. We found that precipitation and temperature changes in Greenland vary across different regions. Our findings suggest that using uniform estimates for temperature and precipitation for modelling the response of the ice sheet can overestimate ice loss in Greenland. Therefore, this study highlights the need for spatially resolved data in predicting the ice sheet's future.

NASA scientific balloon flights to lift off from Antarctica

NASA's Scientific Balloon Program has returned to Antarctica's icy expanse to kick off the annual Antarctic Long-Duration Balloon Campaign, where two balloon flights will carry a total of nine missions to near space. Launch operations will begin mid-December from the agency's Long Duration Balloon camp located near the U.S. National Science Foundation's McMurdo Station on the Ross Ice Shelf.

Seasonal snow cover indicators in coastal Greenland from in situ observations, a climate model, and reanalysis

Seasonal snow cover indicators in coastal Greenland from in situ observations, a climate model, and reanalysis Jorrit van der Schot, Jakob Abermann, Tiago Silva, Kerstin Rasmussen, Michael Winkler, Kirsty Langley, and Wolfgang Schöner The Cryosphere, 18, 5803–5823, https://doi.org/10.5194/tc-18-5803-2024, 2024 We present snow data from nine locations in coastal Greenland. We show that a reanalysis product (CARRA) simulates seasonal snow characteristics better than a regional climate model (RACMO). CARRA output matches particularly well with our reference dataset when we look at the maximum snow water equivalent and the snow cover end date. We show that seasonal snow in coastal Greenland has large spatial and temporal variability and find little evidence of trends in snow cover characteristics.

Quantifying the buttressing contribution of landfast sea ice and melange to Crane Glacier, Antarctic Peninsula

Quantifying the buttressing contribution of landfast sea ice and melange to Crane Glacier, Antarctic Peninsula Richard Parsons, Sainan Sun, G. Hilmar Gudmundsson, Jan Wuite, and Thomas Nagler The Cryosphere, 18, 5789–5801, https://doi.org/10.5194/tc-18-5789-2024, 2024 In 2022, multi-year landfast sea ice in Antarctica's Larsen B embayment disintegrated, after which time an increase in the rate at which Crane Glacier discharged ice into the ocean was observed. As the fast ice was joined to the glacier terminus, it could provide resistance against the glacier's flow, slowing down the rate of ice discharge. We used numerical modelling to quantify this resistive stress and found that the fast ice provided significant support to Crane prior to its disintegration.

Dual-frequency radar observations of snowmelt processes on Antarctic perennial sea ice by CFOSCAT and ASCAT

Dual-frequency radar observations of snowmelt processes on Antarctic perennial sea ice by CFOSCAT and ASCAT Rui Xu, Chaofang Zhao, Stefanie Arndt, and Christian Haas The Cryosphere, 18, 5769–5788, https://doi.org/10.5194/tc-18-5769-2024, 2024 The onset of snowmelt on Antarctic sea ice is an important indicator of sea ice change. In this study, we used two radar scatterometers to detect the onset of snowmelt on perennial Antarctic sea ice. Results show that since 2007, snowmelt onset has demonstrated strong interannual and regional variabilities. We also found that the difference in snowmelt onsets between the two scatterometers is closely related to snow metamorphism.

Exploring how Sentinel-1 wet-snow maps can inform fully distributed physically based snowpack models

Exploring how Sentinel-1 wet-snow maps can inform fully distributed physically based snowpack models Bertrand Cluzet, Jan Magnusson, Louis Quéno, Giulia Mazzotti, Rebecca Mott, and Tobias Jonas The Cryosphere, 18, 5753–5767, https://doi.org/10.5194/tc-18-5753-2024, 2024 We use novel wet-snow maps from Sentinel-1 to evaluate simulations of a snow-hydrological model over Switzerland. These data are complementary to available in situ snow depth observations as they capture a broad diversity of topographic conditions. Wet-snow maps allow us to detect a delayed melt onset in the model, which we resolve thanks to an improved parametrization. This paves the way to further evaluation, calibration, and data assimilation using wet-snow maps.

Enigmatic Alpine avalanches to get a boost as Earth warms

Nature, Published online: 11 December 2024; doi:10.1038/d41586-024-04009-6

Seals strategically scoot around the seas on icebergs

Harbor seals in icy regions use icebergs shed by glaciers as safe platforms to give birth, care for young and molt. New research finds that as glaciers change with the climate, the resulting changes in size, speed and number of icebergs affect seals' critical frozen habitat. Mother seals prefer stable, slower-moving bergs for giving birth and caring for newborn pups, while in the molting season, they and the rest of the seal population favor speedier ice near the best foraging grounds.

Bighorn sheep face death by avalanche in Sierra Nevada range

Snow cover in the Sierra Nevada is expected to shrink overall as the climate warms, but avalanche frequency could remain the same or even increase at high elevations. That's bad news for bighorn sheep that live there, according to new research.

Antarctica's irregular heartbeat shows signs of rapid melting

Geoscientists have created a new climate record for early Antarctic ice ages. It reveals that the early Antarctic ice sheet melted more rapidly than previously thought.

Arctic Tundra Has Long Helped Cool Earth. Now, It’s Fueling Warming.

Wildfires and thawing permafrost are causing the region to release more carbon dioxide than its plants remove, probably for the first time in thousands of years.

Arctic tundra now emits planet-warming pollution, federal report finds

Arctic tundra is releasing greenhouse gases into the atmosphere as hotter temperatures melt frozen ground and wildfires increase.

The macronutrient and micronutrient (iron and manganese) content of icebergs

The macronutrient and micronutrient (iron and manganese) content of icebergs Jana Krause, Dustin Carroll, Juan Höfer, Jeremy Donaire, Eric P. Achterberg, Emilio Alarcón, Te Liu, Lorenz Meire, Kechen Zhu, and Mark J. Hopwood The Cryosphere, 18, 5735–5752, https://doi.org/10.5194/tc-18-5735-2024, 2024 Here we analysed calved ice samples from both the Arctic and Antarctic to assess the variability in the composition of iceberg meltwater. Our results suggest that low concentrations of nitrate and phosphate in ice are primarily from the ice matrix, whereas sediment-rich layers impart a low concentration of silica and modest concentrations of iron and manganese. At a global scale, there are very limited differences in the nutrient composition of ice.

NASA's IXPE details shapes of structures at a newly discovered black hole

NASA's IXPE (Imaging X-ray Polarimetry Explorer) has helped astronomers better understand the shapes of structures essential to a black hole—specifically, the disk of material swirling around it and the shifting plasma region called the corona.

Record-low Antarctic sea ice can be explained and forecast months out by patterns in winds

Researchers show that the all-time record low in winter sea ice extent in 2023 can be explained by warm Southern Ocean conditions and patterns in the winds that circled Antarctica months earlier, allowing forecasts for sea ice coverage around the South Pole to be generated six or more months in advance. This could support regional and global weather and climate models.

'This was preventable’: Corporate world shudders at new risks after slaying of UnitedHealthcare CEO

Threats against corporations have been rising for years, fueled in part by the echo chamber of social media and an increasingly polarized political environment.

Desert ants use the polarity of the geomagnetic field for navigation

Desert ants of the Cataglyphis nodus species use the Earth's magnetic field for spatial orientation, but rely on a different component of the field than other insects. The survey suggests that the ants also use a different mechanism for magnetoreception than most insects studied to date, including the famous monarch butterflies. The researchers suspect that magnetoreception in desert ants is based on a mechanism involving tiny particles of the iron oxide mineral magnetite or other magnetic particles.

Spring-water temperature suggests widespread occurrence of Alpine permafrost in pseudo-relict rock glaciers

Spring-water temperature suggests widespread occurrence of Alpine permafrost in pseudo-relict rock glaciers Luca Carturan, Giulia Zuecco, Angela Andreotti, Jacopo Boaga, Costanza Morino, Mirko Pavoni, Roberto Seppi, Monica Tolotti, Thomas Zanoner, and Matteo Zumiani The Cryosphere, 18, 5713–5733, https://doi.org/10.5194/tc-18-5713-2024, 2024 Pseudo-relict rock glaciers look relict but contain patches of permafrost. They are poorly known in terms of permafrost content, spatial distribution and frequency. Here we use spring-water temperature for a preliminary estimate of the permafrost presence in rock glaciers of a 795 km2 catchment in the Italian Alps. The results show that ~50 % of rock glaciers classified as relict might be pseudo-relict and might contain ~20 % of the ice stored in the rock glaciers in the study area.

Multi-physics ensemble modelling of Arctic tundra snowpack properties

Multi-physics ensemble modelling of Arctic tundra snowpack properties Georgina J. Woolley, Nick Rutter, Leanne Wake, Vincent Vionnet, Chris Derksen, Richard Essery, Philip Marsh, Rosamond Tutton, Branden Walker, Matthieu Lafaysse, and David Pritchard The Cryosphere, 18, 5685–5711, https://doi.org/10.5194/tc-18-5685-2024, 2024 Parameterisations of Arctic snow processes were implemented into the multi-physics ensemble version of the snow model Crocus (embedded within the Soil, Vegetation, and Snow version 2 land surface model) and evaluated at an Arctic tundra site. Optimal combinations of parameterisations that improved the simulation of density and specific surface area featured modifications that raise wind speeds to increase compaction in surface layers, prevent snowdrift, and increase viscosity in basal layers.

Saving ‘old and wise’ animals vital for species’ survival, say scientists

Hunting bigger, more experienced animals eradicates memories and knowledge crucial to group survival, research suggests

It’s not just humans who get wiser as they age – animals do too, according to a growing body of research. The bigmouth buffalo fish can reach 127 years old, the Greenland shark 392, and some sponges can live for 10,000 years or more. And age is not just a number: as animals get older they behave differently depending on their life experiences, gain richer knowledge of their environment, and often pass it on to younger members of their group, researchers say.

The problem is, we are killing off these older creatures. “Earth’s old animals are in decline,” researchers warned in a paper published in Science last month, which analysed more than 9,000 peer-reviewed papers. Few animals make it to old age, and the ones that do are vulnerable to being hunted or harvested by humans, because they are the biggest or have, for example, the largest antlers, horns or tusks.

Earth from Space: First seasonal snow

Image: This Copernicus Sentinel-2 image from 21 November 2024 captures the first snow of the season over Denmark and southern Sweden.

Impacts of differing melt regimes on satellite radar waveforms and elevation retrievals

Impacts of differing melt regimes on satellite radar waveforms and elevation retrievals Alexander C. Ronan, Robert L. Hawley, and Jonathan W. Chipman The Cryosphere, 18, 5673–5683, https://doi.org/10.5194/tc-18-5673-2024, 2024 We generate a 2010–2021 time series of CryoSat-2 waveform shape metrics on the Greenland Ice Sheet, and we compare it to CryoSat-2 elevation data to investigate the reliability of two algorithms used to derive elevations from the SIRAL radar altimeter. Retracked elevations are found to depend on a waveform's leading-edge width in the dry-snow zone. The study indicates that retracking algorithms must consider significant climate events and snow conditions when assessing elevation change.

Rapid surge in global warming mainly due to reduced planetary albedo

Rising sea levels, melting glaciers, heatwaves at sea -- 2023 set a number of alarming new records. The global mean temperature also rose to nearly 1.5 degrees above the preindustrial level, another record. Seeking to identify the causes of this sudden rise has proven a challenge for researchers. After all, factoring in the effects of anthropogenic influences like the accumulation of greenhouse gases in the atmosphere, of the weather phenomenon El Nino, and of natural events like volcanic eruptions, can account for a major portion of the warming. But doing so still leaves a gap of roughly 0.2 degrees Celsius, which has never been satisfactorily explained. A team puts forward a possible explanation for the rise in global mean temperature: our planet has become less reflective because certain types of clouds have declined.

Canada man jumps on polar bear to defend wife from attack

The man suffered serious but non-life threatening injuries during the incident in the country's far north.

Reanalysis of the longest mass balance series in Himalaya using a nonlinear model: Chhota Shigri Glacier (India)

Reanalysis of the longest mass balance series in Himalaya using a nonlinear model: Chhota Shigri Glacier (India) Mohd Farooq Azam, Christian Vincent, Smriti Srivastava, Etienne Berthier, Patrick Wagnon, Himanshu Kaushik, Md. Arif Hussain, Manoj Kumar Munda, Arindan Mandal, and Alagappan Ramanathan The Cryosphere, 18, 5653–5672, https://doi.org/10.5194/tc-18-5653-2024, 2024 Mass balance series on Chhota Shigri Glacier has been reanalysed by combining the traditional mass balance reanalysis framework and a nonlinear model. The nonlinear model is preferred over traditional glaciological methods to compute the mass balances, as the former can capture the spatiotemporal variability in point mass balances from a heterogeneous in situ point mass balance network. The nonlinear model outperforms the traditional method and agrees better with the geodetic estimates.

Brief communication: New perspectives on the skill of modelled sea ice trends in light of recent Antarctic sea ice loss

Brief communication: New perspectives on the skill of modelled sea ice trends in light of recent Antarctic sea ice loss Caroline R. Holmes, Thomas J. Bracegirdle, Paul R. Holland, Julienne Stroeve, and Jeremy Wilkinson The Cryosphere, 18, 5641–5652, https://doi.org/10.5194/tc-18-5641-2024, 2024 Until recently, satellite data showed an increase in Antarctic sea ice area since 1979, but climate models simulated a decrease over this period. This mismatch was one reason for low confidence in model projections of 21st-century sea ice loss. We show that following low Antarctic sea ice in 2022 and 2023, we can no longer conclude that modelled and observed trends differ. However, differences in the manner of the decline mean that model sea ice projections should still be viewed with caution.

Brief communication: RADIX (Rapid Access Drilling and Ice eXtraction) dust logger test in the EastGRIP (East Greenland Ice-core Project) hole

Brief communication: RADIX (Rapid Access Drilling and Ice eXtraction) dust logger test in the EastGRIP (East Greenland Ice-core Project) hole Jakob Schwander, Thomas F. Stocker, Remo Walther, Samuel Marending, Tobias Erhardt, Chantal Zeppenfeld, and Jürg Jost The Cryosphere, 18, 5613–5617, https://doi.org/10.5194/tc-18-5613-2024, 2024 The RADIX (Rapid Access Drilling and Ice eXtraction) optical dust logger is part of the exploratory 20 mm drilling system at the University of Bern and is inserted into the hole after drilling. Temperature and attitude sensors were successfully tested but not the dust sensor, as no RADIX hole reached the required bubble-free ice. In 2023, we tested the logger with an adapter for the deep borehole of the East Greenland Ice-core Project and obtained a good Late Glacial–Early Holocene dust record.

Use of multiple reference data sources to cross-validate gridded snow water equivalent products over North America

Use of multiple reference data sources to cross-validate gridded snow water equivalent products over North America Colleen Mortimer, Lawrence Mudryk, Eunsang Cho, Chris Derksen, Mike Brady, and Carrie Vuyovich The Cryosphere, 18, 5619–5639, https://doi.org/10.5194/tc-18-5619-2024, 2024 Ground measurements of snow water equivalent (SWE) are vital for understanding the accuracy of large-scale estimates from satellites and climate models. We compare two types of measurements – snow courses and airborne gamma SWE estimates – and analyze how measurement type impacts the accuracy assessment of gridded SWE products. We use this analysis to produce a combined reference SWE dataset for North America, applicable for future gridded SWE product evaluations and other applications.

Swelling streams -- climate change causes more sediment in high-mountain rivers

Many high-mountain rivers in Asia transport more sediment downstream compared to a few years ago. Changes in sediment levels have a particularly strong impact on agriculture, water quality, flood management, and hydropower generation. A study demonstrates the interacting roles of glaciers, vegetation, precipitation, and slope in mobilizing sediment and controlling the current sediment transport in rivers. In order to counteract climate change, the authors call for a systematic approach for the entire catchment area of rivers in the high mountains.

Could melting ice wake up Antarctica’s volcanoes?

Researchers probe immediate and long-term threats at two of continent’s biggest magmatic tinderboxes

Alaska's changing environment

The University of Alaska Fairbanks released a new report this week highlighting environmental changes and extremes that impact Alaskans and their livelihoods. 'Alaska's Changing Environment' provides people with timely, reliable and understandable information on topics ranging from temperature and precipitation changes to salmon and polar bears.

Countdown to an ice-free Arctic: New research warns of accelerated timelines

Scientists demonstrate how a series of extreme weather events could lead to the Arctic's first ice-free day within just a few years.

Linking glacier retreat with climate change on the Tibetan Plateau through satellite remote sensing

Linking glacier retreat with climate change on the Tibetan Plateau through satellite remote sensing Fumeng Zhao, Wenping Gong, Silvia Bianchini, and Zhongkang Yang The Cryosphere, 18, 5595–5612, https://doi.org/10.5194/tc-18-5595-2024, 2024 Glacier retreat patterns and climatic drivers on the Tibetan Plateau are uncertain at finer resolutions. This study introduces a new glacier-mapping method covering 1988 to 2022, using downscaled air temperature and precipitation data. It quantifies the impacts of annual and seasonal temperature and precipitation on retreat. Results show rapid and varied retreat: annual temperature and spring precipitation influence retreat in the west and northwest, respectively.

The influence of firn layer material properties on surface crevasse propagation in glaciers and ice shelves

The influence of firn layer material properties on surface crevasse propagation in glaciers and ice shelves Theo Clayton, Ravindra Duddu, Tim Hageman, and Emilio Martínez-Pañeda The Cryosphere, 18, 5573–5593, https://doi.org/10.5194/tc-18-5573-2024, 2024 We develop and validate new analytical solutions that quantitatively consider how the properties of ice vary along the depth of ice shelves and that can be readily used in existing ice sheet models. Depth-varying firn properties are found to have a profound impact on ice sheet fracture and calving events. Our results show that grounded glaciers are less vulnerable than previously anticipated, while floating ice shelves are significantly more vulnerable to fracture and calving.

Ice-shelf disintegration in East Antarctica

Nature Geoscience, Published online: 03 December 2024; doi:10.1038/s41561-024-01607-x

Multi-decadal collapse of East Antarctica’s Conger–Glenzer Ice Shelf

Nature Geoscience, Published online: 03 December 2024; doi:10.1038/s41561-024-01582-3

Norway hits pause on controversial deep-sea mining plans

Norway has shelved plans to open a vast ocean area at the bottom of the Arctic for commercial-scale deep-sea mining.

Norway suspends controversial deep-sea mining plan

Oslo's plan to open up its Arctic seabed for mining prompted stark environmental opposition.

Top Wall Street analysts pick 3 stocks for their attractive prospects

TipRanks' analyst ranking service pinpoints Wall Street's best-performing stocks, including ServiceNow and Snowflake.

I interviewed 70 parents who raised highly successful adults—their top 4 regrets: 'I shouldn’t have fixed things for them'

"Raising an Entrepreneur" author Margot Machol Bisnow, who interviewed 70 parents who raised successful adults, reveals what they would have done differently.

The Pléiades Glacier Observatory: high-resolution digital elevation models and ortho-imagery to monitor glacier change

The Pléiades Glacier Observatory: high-resolution digital elevation models and ortho-imagery to monitor glacier change Etienne Berthier, Jérôme Lebreton, Delphine Fontannaz, Steven Hosford, Joaquín Muñoz-Cobo Belart, Fanny Brun, Liss M. Andreassen, Brian Menounos, and Charlotte Blondel The Cryosphere, 18, 5551–5571, https://doi.org/10.5194/tc-18-5551-2024, 2024 Repeat elevation measurements are crucial for monitoring glacier health and to understand how glaciers affect river flows and sea level. Until recently, high-resolution elevation data were mostly available for polar regions and High Mountain Asia. Our project, the Pléiades Glacier Observatory, now provides high-resolution topographies of 140 glacier sites worldwide. This is a novel and open dataset to monitor the impact of climate change on glaciers at high resolution and accuracy.

The future of Upernavik Isstrøm through the ISMIP6 framework: sensitivity analysis and Bayesian calibration of ensemble prediction

The future of Upernavik Isstrøm through the ISMIP6 framework: sensitivity analysis and Bayesian calibration of ensemble prediction Eliot Jager, Fabien Gillet-Chaulet, Nicolas Champollion, Romain Millan, Heiko Goelzer, and Jérémie Mouginot The Cryosphere, 18, 5519–5550, https://doi.org/10.5194/tc-18-5519-2024, 2024 Inspired by a previous intercomparison framework, our study better constrains uncertainties in glacier evolution using an innovative method to validate Bayesian calibration. Upernavik Isstrøm, one of Greenland's largest glaciers, has lost significant mass since 1985. By integrating observational data, climate models, human emissions, and internal model parameters, we project its evolution until 2100. We show that future human emissions are the main source of uncertainty in 2100, making up half.

Inefficient transfer of diatoms through the subpolar Southern Ocean twilight zone

Nature Geoscience, Published online: 28 November 2024; doi:10.1038/s41561-024-01602-2

The melting of Greenland: A climate challenge with major implications for the 21st century

The melting of Greenland is accelerating, with an estimated loss of between 964 and 1735 gigatons of ice per year by 2100 in a scenario of high greenhouse gas emissions (SSP585), according to three regional climate models. This melting will lead to a rise in sea levels of up to one meter, threatening millions of people in coastal areas.

'Arctic outbreak' for parts of US as millions travel for Thanksgiving

Temperatures could plummet to -40C in the northern Plains and Upper Midwest during a busy period for travel.

Seoul blanketed by heaviest November snow on record

At least one person is reported to have died as a result of the weather, which has also grounded flights.

Impact of climate change on snow avalanche activity in the Swiss Alps

Impact of climate change on snow avalanche activity in the Swiss Alps Stephanie Mayer, Martin Hendrick, Adrien Michel, Bettina Richter, Jürg Schweizer, Heini Wernli, and Alec van Herwijnen The Cryosphere, 18, 5495–5517, https://doi.org/10.5194/tc-18-5495-2024, 2024 Understanding the impact of climate change on snow avalanche activity is crucial for safeguarding lives and infrastructure. Here, we project changes in avalanche activity in the Swiss Alps throughout the 21st century. Our findings reveal elevation-dependent patterns of change, indicating a decrease in dry-snow avalanches alongside an increase in wet-snow avalanches at elevations above the current treeline. These results underscore the necessity to revisit measures for avalanche risk mitigation.

Accumulation by avalanches as a significant contributor to the mass balance of a peripheral glacier of Greenland

Accumulation by avalanches as a significant contributor to the mass balance of a peripheral glacier of Greenland Bernhard Hynek, Daniel Binder, Michele Citterio, Signe Hillerup Larsen, Jakob Abermann, Geert Verhoeven, Elke Ludewig, and Wolfgang Schöner The Cryosphere, 18, 5481–5494, https://doi.org/10.5194/tc-18-5481-2024, 2024 An avalanche event in February 2018 caused thick snow deposits on Freya Glacier, a peripheral mountain glacier in northeastern Greenland. The avalanche deposits contributed significantly to the mass balance, leaving a strong imprint in the elevation changes in 2013–2021. The 8-year geodetic mass balance (2013–2021) of the glacier is positive, whereas previous estimates by direct measurements were negative and now turned out to have a negative bias. 

Unexplained heat-wave 'hotspots' are popping up across the globe

A striking new phenomenon is emerging: distinct regions are seeing repeated heat waves that are so extreme, they fall far beyond what any model of global warming can predict or explain. A new study provides the first worldwide map of such regions, which show up on every continent except Antarctica like giant, angry skin blotches.

Researchers show complex relationship between Arctic warming and Arctic dust

A study found that dust from snow- and ice-free areas of the Arctic could be an important contributor to climate change in the region. Higher levels of dust help promote the formation of ice crystals in the clouds, which weakens the efficiency of clouds to contain more liquid droplets and fewer ice crystals by Arctic warming.

Delay and pay: Climate tipping point costs quadruple after waiting

The cost of reversing the effects of climate change -- restoring melted polar sea ice, for example -- quickly climbs nearly fourfold soon after a tipping point is crossed, according to new work. Much work has been done to explore the environmental costs tied to climate change. But this new study marks the first time researchers have quantified the costs of controlling tipping points before and after they unfold.

Under-ice species at risk as Arctic warms

'Specialist' lifeforms that live under Arctic sea ice are at risk as the ice retreats, new research shows.

CPOM in Iceland: Drones study ice and proglacial lakes on the frontline of climate change

A team from the UK Centre for Polar Observation and Modelling (CPOM) recently spent six days surveying glaciers and proglacial lakes in Iceland. Although there were a lot of early mornings, harsh weather and unexpected challenges, they had a fantastic time, gathered some excellent data and got to see the [...]

Daily briefing: NASA finds secret ice base in Greenland

Nature, Published online: 26 November 2024; doi:10.1038/d41586-024-03887-0

Modeling saline-fluid flow through subglacial channels

Modeling saline-fluid flow through subglacial channels Amy Jenson, Mark Skidmore, Lucas Beem, Martin Truffer, and Scott McCalla The Cryosphere, 18, 5451–5464, https://doi.org/10.5194/tc-18-5451-2024, 2024 Water in some glacier environments contains salt, which increases its density and lowers its freezing point, allowing saline water to exist where freshwater cannot. Previous subglacial hydrology models do not consider saline fluid. We model the flow of saline fluid from a subglacial lake through a circular channel at the glacier bed, finding that higher salinities lead to less melting at the channel walls and lower discharge rates. We also observe the impact of increased fluid density on flow.   

Assessing supraglacial lake depth using ICESat-2, Sentinel-2, TanDEM-X, and in situ sonar measurements over Northeast and Southwest Greenland

Assessing supraglacial lake depth using ICESat-2, Sentinel-2, TanDEM-X, and in situ sonar measurements over Northeast and Southwest Greenland Katrina Lutz, Lily Bever, Christian Sommer, Thorsten Seehaus, Angelika Humbert, Mirko Scheinert, and Matthias Braun The Cryosphere, 18, 5431–5449, https://doi.org/10.5194/tc-18-5431-2024, 2024 The estimation of the amount of water found within supraglacial lakes is important for understanding how much water is lost from glaciers each year. Here, we develop two new methods for estimating supraglacial lake volume that can be easily applied on a large scale. Furthermore, we compare these methods to two previously developed methods in order to determine when it is best to use each method. Finally, three of these methods are applied to peak melt dates over an area in Northeast Greenland.

Evaluating snow depth retrievals from Sentinel-1 volume scattering over NASA SnowEx sites

Evaluating snow depth retrievals from Sentinel-1 volume scattering over NASA SnowEx sites Zachary Hoppinen, Ross T. Palomaki, George Brencher, Devon Dunmire, Eric Gagliano, Adrian Marziliano, Jack Tarricone, and Hans-Peter Marshall The Cryosphere, 18, 5407–5430, https://doi.org/10.5194/tc-18-5407-2024, 2024 This study uses radar imagery from the Sentinel-1 satellite to derive snow depth from increases in the returning energy. These retrieved depths are then compared to nine lidar-derived snow depths across the western United State to assess the ability of this technique to be used to monitor global snow distributions. We also qualitatively compare the changes in underlying Sentinel-1 amplitudes against both the total lidar snow depths and nine automated snow monitoring stations.

Atmospheric river dumps snow and record rain on California

The weather event has multiplied damages from the 'bomb cyclone' seen in the US north-west earlier this week.

In Patagonia, more snow could protect glaciers from melt -- but only if we curb greenhouse gas emissions soon

In an era of dwindling glaciers, Southern Patagonia has managed to hold on to a surprising amount of its ice. But, a new study suggests that this protective effect might be pushed up against its limits soon.

Antarctica’s first known amber whispers of a vanished rainforest

Nature, Published online: 22 November 2024; doi:10.1038/d41586-024-03803-6

Copernicus Sentinel-1: radar vision for Copernicus

Video: 00:07:25

Meet Copernicus Sentinel-1 – this ground-breaking mission delivers continuous, all-weather, day-and-night imaging for land, ice and maritime monitoring. 

Equipped with state-of-the-art C-band synthetic aperture radar (SAR), Sentinel-1 captures high-resolution data around the clock, in any weather, making it indispensable for detecting the subtle changes on Earth’s surface that remain hidden from the human eye.

Sentinel-1 data serves a multitude of critical applications: from ensuring the safety and efficiency of maritime traffic, tracking sea ice and icebergs, to monitoring structural integrity and natural hazards, such as earthquakes, landslides and volcanic activity. 

Its enhanced radar technology provides precises precise information on ground movement, which is critical for urban planning, infrastructure resilience, subsidence risk assessment and geohazard monitoring. 

Through consistent, long-term data collection, Sentinel-1 serves as a global asset, essential for environmental and safety monitoring worldwide. The mission is a beacon of innovation, advancing our understanding of our planet’s dynamic landscape.

This video features interviews with Mark Drinkwater, Head of Mission Sciences Division at ESA, Ramon Torres Cuesta, Sentinel-1 Project Manager at ESA and Julia Kubanek, Sentinel-1 Mission Scientist at ESA.

Hear me out: RFK could be a transformational health secretary | Neil Barsky

RFK Jr has articulated what our Democratic and Republican leaders have largely ignored: our healthcare system is a national disgrace hiding in plain sight

Among the cast of characters poised to join the Trump administration, no one is as exasperating, polarizing or potentially dangerous as Robert F Kennedy Jr. But in a twist that is emblematic of our times, no single nominee has the potential to do as much good for the American people.

Bear with me. RFK Jr has been rightly pilloried for promoting a litany of theories linking vaccines with autism, chemicals in the water supply to gender identity, how people contract Aids and saying the Covid-19 vaccine, which in fact stemmed the deadliest pandemic of our lifetimes, was itself “the deadliest vaccine ever made”. He claimed Covid-19 was meant to target certain ethnic groups, Black people and Caucasians, while sparing Asians and Jewish people.

Unravelling the sources of uncertainty in glacier runoff projections in the Patagonian Andes (40–56° S)

Unravelling the sources of uncertainty in glacier runoff projections in the Patagonian Andes (40–56° S) Rodrigo Aguayo, Fabien Maussion, Lilian Schuster, Marius Schaefer, Alexis Caro, Patrick Schmitt, Jonathan Mackay, Lizz Ultee, Jorge Leon-Muñoz, and Mauricio Aguayo The Cryosphere, 18, 5383–5406, https://doi.org/10.5194/tc-18-5383-2024, 2024 Predicting how much water will come from glaciers in the future is a complex task, and there are many factors that make it uncertain. Using a glacier model, we explored 1920 scenarios for each glacier in the Patagonian Andes. We found that the choice of the historical climate data was the most important factor, while other factors such as different data sources, climate models and emission scenarios played a smaller role.

Bounded and categorized: targeting data assimilation for sea ice fractional coverage and nonnegative quantities in a single-column multi-category sea ice model

Bounded and categorized: targeting data assimilation for sea ice fractional coverage and nonnegative quantities in a single-column multi-category sea ice model Molly M. Wieringa, Christopher Riedel, Jeffrey L. Anderson, and Cecilia M. Bitz The Cryosphere, 18, 5365–5382, https://doi.org/10.5194/tc-18-5365-2024, 2024 Statistically combining models and observations with data assimilation (DA) can improve sea ice forecasts but must address several challenges, including irregularity in ice thickness and coverage over the ocean. Using a sea ice column model, we show that novel, bounds-aware DA methods outperform traditional methods for sea ice. Additionally, thickness observations at sub-grid scales improve modeled ice estimates of both thick and thin ice, a finding relevant for forecasting applications.

Using deep learning and multi-source remote sensing images to map landlocked lakes in Antarctica

Using deep learning and multi-source remote sensing images to map landlocked lakes in Antarctica Anyao Jiang, Xin Meng, Yan Huang, and Guitao Shi The Cryosphere, 18, 5347–5364, https://doi.org/10.5194/tc-18-5347-2024, 2024 Landlocked lakes are crucial to the Antarctic ecosystem and sensitive to climate change. Limited research on their distribution prompted us to develop an automated detection process using deep learning and multi-source satellite imagery. This allowed us to accurately determine the landlocked lake open water (LLOW) area in Antarctica, generating high-resolution time series data. We find that the changes in positive and negative degree days predominantly drive variations in the LLOW area.

‘The land is tearing itself apart’: life on a collapsing Arctic isle

On Qikiqtaruk, off Canada, researchers at the frontier of climate change are seeing its rich ecology slide into the sea as the melting permafrost leaves little behind

Last summer, the western Arctic was uncomfortably hot. Smoke from Canada’s wildfires hung thick in the air, and swarms of mosquitoes searched for exposed skin. It was a maddening combination that left researchers on Qikiqtaruk, an island off the north coast of the Yukon, desperate for relief.

And so on a late July afternoon, a team of Canadian scientists dived into the Beaufort Sea, bobbing and splashing in a sheltered bay for nearly two hours. Later, as they lay sprawled on a beach, huge chunks of the island they were studying slid into the ocean.

Snowflake shares pop 19% on earnings and revenue beat

Snowflake reported better-than-expected results on the top and bottom lines.

Canada's first moon rover will soon have a name as it prepares to explore a hostile lunar region

The Canadian Space Agency announced a competition today to name Canada's first-ever rover mission to the moon. This unmanned mission will explore the south polar region of the moon to search for water ice and explore its unique geology.

Deadly bomb cyclone cuts power for thousands in US north-west

The storm is bringing damaging winds, snow and excessive rainfall that could lead to mudslides.

Plantwatch: Arctic microalgae perform photosynthesis in near darkness

Unlocking secrets of how the algae survive could help extend growing seasons for crop plants at high latitudes

Plants left for too long in the dark usually turn sickly yellow and die, but scientists were astonished to discover tiny microalgae in the Arctic Ocean down to 50 metres deep can perform photosynthesis in near darkness.

The microalgae were at 88-degrees north and started photosynthesising in late March, only a few days after the long winter polar night came to an end at this latitude. The sun was barely poking up above the horizon and the sea was still covered in snow and ice, barely allowing any light to pass through. Typical light conditions outside on a clear day in Europe are more than 37,000-50,000 times the amount of light required by these Arctic microalgae.

Arctic freshwater anomaly transiting to the North Atlantic delayed within a buffer zone

Nature Geoscience, Published online: 20 November 2024; doi:10.1038/s41561-024-01592-1

Trion sensing of a zero-field composite Fermi liquid

Nature, Published online: 20 November 2024; doi:10.1038/s41586-024-08134-0

Extending the Center for Western Weather and Water Extremes (CW3E) atmospheric river scale to the polar regions

Extending the Center for Western Weather and Water Extremes (CW3E) atmospheric river scale to the polar regions Zhenhai Zhang, F. Martin Ralph, Xun Zou, Brian Kawzenuk, Minghua Zheng, Irina V. Gorodetskaya, Penny M. Rowe, and David H. Bromwich The Cryosphere, 18, 5239–5258, https://doi.org/10.5194/tc-18-5239-2024, 2024 Atmospheric rivers (ARs) are long, narrow corridors of strong water vapor transport in the atmosphere. ARs play an important role in extreme weather in polar regions, including heavy rain and/or snow, heat waves, and surface melt. The standard AR scale is developed based on the midlatitude climate and is insufficient for polar regions. This paper introduces an extended version of the AR scale tuned to polar regions, aiming to quantify polar ARs objectively based on their strength and impact.

Pan-Arctic sea ice concentration from SAR and passive microwave

Pan-Arctic sea ice concentration from SAR and passive microwave Tore Wulf, Jørgen Buus-Hinkler, Suman Singha, Hoyeon Shi, and Matilde Brandt Kreiner The Cryosphere, 18, 5277–5300, https://doi.org/10.5194/tc-18-5277-2024, 2024 Here, we present ASIP: a new and comprehensive deep-learning-based methodology to retrieve high-resolution sea ice concentration with accompanying well-calibrated uncertainties from satellite-based active and passive microwave observations at a pan-Arctic scale for all seasons. In a comparative study against pan-Arctic ice charts and well-established passive-microwave-based sea ice products, we show that ASIP generalizes well to the pan-Arctic region.

Two-way coupling between ice flow and channelized subglacial drainage enhances modeled marine-ice-sheet retreat

Two-way coupling between ice flow and channelized subglacial drainage enhances modeled marine-ice-sheet retreat George Lu and Jonathan Kingslake The Cryosphere, 18, 5301–5321, https://doi.org/10.5194/tc-18-5301-2024, 2024 Water below ice sheets affects ice-sheet motion, while the evolution of ice sheets likewise affects the water below. We create a model that allows for water and ice to affect each other and use it to see how this coupling or lack thereof may impact ice-sheet retreat. We find that coupling an evolving water system with the ice sheet results in more retreat than if we assume unchanging conditions under the ice, which indicates a need to better represent the effects of water in ice-sheet models.

Land surface temperature trends derived from Landsat imagery in the Swiss Alps

Land surface temperature trends derived from Landsat imagery in the Swiss Alps Deniz Tobias Gök, Dirk Scherler, and Hendrik Wulf The Cryosphere, 18, 5259–5276, https://doi.org/10.5194/tc-18-5259-2024, 2024 We derived Landsat Collection 2 land surface temperature (LST) trends in the Swiss Alps using a harmonic model with a linear trend. Validation with LST data from 119 high-altitude weather stations yielded robust results, but Landsat LST trends are biased due to unstable acquisition times. The bias varies with topographic slope and aspect. We discuss its origin and propose a simple correction method in relation to modeled changes in shortwave radiation.

Unlocking the potential of melting calorimetry: a field protocol for liquid water content measurement in snow

Unlocking the potential of melting calorimetry: a field protocol for liquid water content measurement in snow Riccardo Barella, Mathias Bavay, Francesca Carletti, Nicola Ciapponi, Valentina Premier, and Carlo Marin The Cryosphere, 18, 5323–5345, https://doi.org/10.5194/tc-18-5323-2024, 2024 This research revisits a classic scientific technique, melting calorimetry, to measure snow liquid water content. This study shows with a novel uncertainty propagation framework that melting calorimetry, traditionally less trusted than freezing calorimetry, can produce accurate results. The study defines optimal experiment parameters and a robust field protocol. Melting calorimetry has the potential to become a valuable tool for validating other liquid water content measuring techniques.

Space for Shore: Sentinel-1 reveals Arctic glacier retreat

As Arctic temperatures rise, marine-terminating glaciers—especially in places like Svalbard—are undergoing rapid retreat and intensified calving.

The ESA-funded Space for Shore project utilises radar data from the Copernicus Sentinel-1 mission to provide precise, year-over-year insights into glacier retreat and calving intensity, particularly in areas like Kongsfjorden, where notable glaciers are experiencing significant retreat.

Where Glaciers Melt, the Rivers Run Red

As the glaciers of South America retreat, the supply of freshwater is dwindling and its quality is getting worse.

Political shadows cast by the Antarctic curtain

The scientific debate around the installation of a massive underwater curtain to protect Antarctic ice sheets from melting lacks its vital political perspective. A research team argues that the serious questions around authority, sovereignty and security should be addressed proactively by the scientific community to avoid the protected seventh continent becoming the scene or object of international discord.

A Mummified Saber-Toothed Kitten Emerges in Siberia

The Homotherium cub was preserved in Siberian permafrost with its dark fur and flesh intact.

‘Arctic Niño’ might emerge in an ice-free world

Nature Climate Change, Published online: 18 November 2024; doi:10.1038/s41558-024-02175-z

When fire and ice meet

Nature Climate Change, Published online: 18 November 2024; doi:10.1038/s41558-024-02183-z

Scientists find a 35,000-year-old saber-toothed kitten in the Siberian permafrost

The kitten, which was found in Russia's northeastern Sakha Republic, still had fur and whiskers when it was discovered.

Melting glaciers leave homes teetering in valley of jagged mountains

Climate change is altering the landscape of Pakistan's mountain regions, and changing lives forever.

One or many? Exploring the population groups of the largest animal on Earth

Hunted nearly to extinction during 20th century whaling, the Antarctic blue whale, the world's largest animal, went from a population size of roughly 200,000 to little more than 300. The most recent estimate in 2004 put Antarctic blue whales at less than 1% of their pre-whaling levels. A new study shows that, though these whales feed in different ocean basins, they appear to be a single population, information that will help conservation efforts moving forward.

Twenty-first century global glacier evolution under CMIP6 scenarios and the role of glacier-specific observations

Twenty-first century global glacier evolution under CMIP6 scenarios and the role of glacier-specific observations Harry Zekollari, Matthias Huss, Lilian Schuster, Fabien Maussion, David R. Rounce, Rodrigo Aguayo, Nicolas Champollion, Loris Compagno, Romain Hugonnet, Ben Marzeion, Seyedhamidreza Mojtabavi, and Daniel Farinotti The Cryosphere, 18, 5045–5066, https://doi.org/10.5194/tc-18-5045-2024, 2024 Glaciers are major contributors to sea-level rise and act as key water resources. Here, we model the global evolution of glaciers under the latest generation of climate scenarios. We show that the type of observations used for model calibration can strongly affect the projections at the local scale. Our newly projected 21st century global mass loss is higher than the current community estimate as reported in the latest Intergovernmental Panel on Climate Change (IPCC) report.

A framework for automated supraglacial lake detection and depth retrieval in ICESat-2 photon data across the Greenland and Antarctic ice sheets

A framework for automated supraglacial lake detection and depth retrieval in ICESat-2 photon data across the Greenland and Antarctic ice sheets Philipp Sebastian Arndt and Helen Amanda Fricker The Cryosphere, 18, 5173–5206, https://doi.org/10.5194/tc-18-5173-2024, 2024 We develop a method for ice-sheet-scale retrieval of supraglacial meltwater depths using ICESat-2 photon data. We report results for two drainage basins in Greenland and Antarctica during two contrasting melt seasons, where our method reveals a total of 1249 lake segments up to 25 m deep. The large volume and wide variety of accurate depth data that our method provides enable the development of data-driven models of meltwater volumes in satellite imagery.

Probabilistic projections of the Amery Ice Shelf catchment, Antarctica, under conditions of high ice-shelf basal melt

Probabilistic projections of the Amery Ice Shelf catchment, Antarctica, under conditions of high ice-shelf basal melt Sanket Jantre, Matthew J. Hoffman, Nathan M. Urban, Trevor Hillebrand, Mauro Perego, Stephen Price, and John D. Jakeman The Cryosphere, 18, 5207–5238, https://doi.org/10.5194/tc-18-5207-2024, 2024 We investigate potential sea-level rise from Antarctica's Lambert Glacier, once considered stable but now at risk due to projected ocean warming by 2100. Using statistical methods and limited supercomputer simulations, we calibrated our ice-sheet model using three observables. We find that, under high greenhouse gas emissions, glacier retreat could raise sea levels by 46–133 mm by 2300. This study highlights the need for better observations to reduce uncertainty in ice-sheet model projections.

Earth from Space: Clouds or snow?

Image: These two images acquired by Copernicus Sentinel-2 highlight how the mission can help distinguish between clouds and snow.

Hiker discovers first trace of entire prehistoric ecosystem in Italian Alps

Melting snow and ice has revealed footprints of reptiles and amphibians, dating back 280 million years

A hiker in the northern Italian Alps has stumbled across the first trace of what scientists believe to be an entire prehistoric ecosystem, including the well-preserved footprints of reptiles and amphibians, brought to light by the melting of snow and ice induced by the climate crisis.

The discovery in the Valtellina Orobie mountain range in Lombardy dates back 280 million years to the Permian period, the age immediately prior to dinosaurs, scientists say.

Characterization of non-Gaussianity in the snow distributions of various landscapes

Characterization of non-Gaussianity in the snow distributions of various landscapes Noriaki Ohara, Andrew D. Parsekian, Benjamin M. Jones, Rodrigo C. Rangel, Kenneth M. Hinkel, and Rui A. P. Perdigão The Cryosphere, 18, 5139–5152, https://doi.org/10.5194/tc-18-5139-2024, 2024 Snow distribution characterization is essential for accurate snow water estimation for water resource prediction from existing in situ observations and remote-sensing data at a finite spatial resolution. Four different observed snow distribution datasets were analyzed for Gaussianity. We found that non-Gaussianity of snow distribution is a signature of the wind redistribution effect. Generally, seasonal snowpack can be approximated well by a Gaussian distribution for a fully snow-covered area.

Massive mobilization of toxic elements from an intact rock glacier in the central Eastern Alps

Massive mobilization of toxic elements from an intact rock glacier in the central Eastern Alps Hoda Moradi, Gerhard Furrer, Michael Margreth, David Mair, and Christoph Wanner The Cryosphere, 18, 5153–5171, https://doi.org/10.5194/tc-18-5153-2024, 2024 Detailed monitoring of a rock glacier spring in the Eastern Alps showed that more than 1 tonne of toxic solutes, such as aluminum, nickel, and manganese, is mobilized each year from a small permafrost area. The strong mobilization is caused by rock weathering and long-term accumulation of toxic solutes in permafrost ice. Today, climate-change-induced permafrost degradation leads to a quick and focused export in summer. This forms an unexpected, novel hazard for alpine and high-latitude areas.

Increasing aerosol emissions from boreal biomass burning exacerbate Arctic warming

Nature Climate Change, Published online: 14 November 2024; doi:10.1038/s41558-024-02176-y

Faster flowing glaciers could help predict nearby volcanic activity

Glaciers that are within three miles of a volcano move nearly 50% quicker than average, a new study has found, which could help create early warning of future eruptions.

Sensitivity of the future evolution of the Wilkes Subglacial Basin ice sheet to grounding-line melt parameterizations

Sensitivity of the future evolution of the Wilkes Subglacial Basin ice sheet to grounding-line melt parameterizations Yu Wang, Chen Zhao, Rupert Gladstone, Thomas Zwinger, Benjamin K. Galton-Fenzi, and Poul Christoffersen The Cryosphere, 18, 5117–5137, https://doi.org/10.5194/tc-18-5117-2024, 2024 Our research delves into the future evolution of Antarctica's Wilkes Subglacial Basin (WSB) and its potential contribution to sea level rise, focusing on how basal melt is implemented at the grounding line in ice flow models. Our findings suggest that these implementation methods can significantly impact the magnitude of future ice loss projections. Under a high-emission scenario, the WSB ice sheet could undergo massive and rapid retreat between 2200 and 2300.

In greening Arctic, caribou and muskoxen play key role

A new study highlights the importance of caribou and muskoxen to the greening Arctic tundra, linking grazing with plant phenology and abundance in the Arctic tundra.

First amber find on the Antarctic continent

Roughly 90 million years ago, climatic conditions in Antarctica were suitable for resin-producing trees. Researchers have now made the southernmost discovery of amber in the world.

Swirling polar vortices likely exist on the sun, new research finds

Like the Earth, the sun likely has swirling polar vortices, according to new research led by the U.S. National Science Foundation National Center for Atmospheric Research (NSF NCAR). But unlike on Earth, the formation and evolution of these vortices are driven by magnetic fields.

Festival worker to become Antarctic postmaster

George Clarke will staff the most southerly post office in the world, living among a penguin colony.

Emergence of a climate oscillation in the Arctic Ocean due to global warming

Nature Climate Change, Published online: 11 November 2024; doi:10.1038/s41558-024-02171-3

A Warming Climate Continues to Ravage Sea Ice at Both Poles

Even as winter takes hold in the Arctic, sea ice there is growing sluggishly. In Antarctica, summer’s arrival has driven sea ice to near-record lows.

Measurements from 'lost' Seaglider offer new insights into Antarctic ice melting

New research reveals for the first time how a major Antarctic ice shelf has been subjected to increased melting by warming ocean waters over the last four decades. Scientists say the study -- the result of their autonomous Seaglider getting accidentally stuck underneath the Ross Ice Shelf -- suggests this will likely only increase further as climate change drives continued ocean warming.

Application of a regularised Coulomb sliding law to Jakobshavn Isbræ, western Greenland

Application of a regularised Coulomb sliding law to Jakobshavn Isbræ, western Greenland Matt Trevers, Antony J. Payne, and Stephen L. Cornford The Cryosphere, 18, 5101–5115, https://doi.org/10.5194/tc-18-5101-2024, 2024 The form of the friction law which determines the speed of ice sliding over the bedrock remains a major source of uncertainty in ice sheet model projections of future sea level rise. Jakobshavn Isbræ, the fastest-flowing glacier in Greenland, which has undergone significant changes in the last few decades, is an ideal case for testing sliding laws. We find that a regularised Coulomb friction law reproduces the large seasonal and inter-annual flow speed variations most accurately.

Modelling snowpack on ice surfaces with the ORCHIDEE land surface model: application to the Greenland ice sheet

Modelling snowpack on ice surfaces with the ORCHIDEE land surface model: application to the Greenland ice sheet Sylvie Charbit, Christophe Dumas, Fabienne Maignan, Catherine Ottlé, Nina Raoult, Xavier Fettweis, and Philippe Conesa The Cryosphere, 18, 5067–5099, https://doi.org/10.5194/tc-18-5067-2024, 2024 The evolution of the Greenland ice sheet is highly dependent on surface melting and therefore on the processes operating at the snow–atmosphere interface and within the snow cover. Here we present new developments to apply a snow model to the Greenland ice sheet. The performance of this model is analysed in terms of its ability to simulate ablation processes. Our analysis shows that the model performs well when compared with the MAR regional polar atmospheric model.

Microplastics impact cloud formation, likely affecting weather and climate

Scientists have spotted microplastics, tiny pieces of plastic smaller than 5 millimeters, in some of the most pristine environments on Earth, from the depths of the Mariana Trench to the snow on Mt. Everest to the mountaintop clouds of China and Japan. Microplastics have been detected in human brains, the bellies of sea turtles and the roots of plants. Now, research reveals that microplastics in the atmosphere could be affecting weather and climate.

Snow returns to Mount Fuji

Image: Snow returns to Mount Fuji

Laser ablation inductively coupled plasma mass spectrometry measurements for high-resolution chemical ice core analyses with a first application to an ice core from Skytrain Ice Rise (Antarctica)

Laser ablation inductively coupled plasma mass spectrometry measurements for high-resolution chemical ice core analyses with a first application to an ice core from Skytrain Ice Rise (Antarctica) Helene Hoffmann, Jason Day, Rachael H. Rhodes, Mackenzie Grieman, Jack Humby, Isobel Rowell, Christoph Nehrbass-Ahles, Robert Mulvaney, Sally Gibson, and Eric Wolff The Cryosphere, 18, 4993–5013, https://doi.org/10.5194/tc-18-4993-2024, 2024 Ice cores are archives of past atmospheric conditions. In deep and old ice, the layers containing this information get thinned to the millimetre scale or below. We installed a setup for high-resolution (182 μm) chemical impurity measurements in ice cores using the laser ablation technique at the University of Cambridge. In a first application to the Skytrain ice core from Antarctica, we discuss the potential to detect fine-layered structures in ice up to an age of 26 000 years.

Seasonal evolution of the sea ice floe size distribution in the Beaufort Sea from 2 decades of MODIS data

Seasonal evolution of the sea ice floe size distribution in the Beaufort Sea from 2 decades of MODIS data Ellen M. Buckley, Leela Cañuelas, Mary-Louise Timmermans, and Monica M. Wilhelmus The Cryosphere, 18, 5031–5043, https://doi.org/10.5194/tc-18-5031-2024, 2024 Arctic sea ice cover evolves seasonally from large plates separated by long, linear leads in the winter to a mosaic of smaller sea ice floes in the summer. Here, we present a new image segmentation algorithm applied to thousands of images and identify over 9 million individual pieces of ice. We observe the characteristics of the floes and how they evolve throughout the summer as the ice breaks up.

Thwaites Glacier thins and retreats fastest where ice-shelf channels intersect its grounding zone

Thwaites Glacier thins and retreats fastest where ice-shelf channels intersect its grounding zone Allison M. Chartrand, Ian M. Howat, Ian R. Joughin, and Benjamin E. Smith The Cryosphere, 18, 4971–4992, https://doi.org/10.5194/tc-18-4971-2024, 2024 This study uses high-resolution remote-sensing data to show that shrinking of the West Antarctic Thwaites Glacier’s ice shelf (floating extension) is exacerbated by several sub-ice-shelf meltwater channels that form as the glacier transitions from full contact with the seafloor to fully floating. In mapping these channels, the position of the transition zone, and thinning rates of the Thwaites Glacier, this work elucidates important processes driving its rapid contribution to sea level rise.

Improved snow property retrievals by solving for topography in the inversion of at-sensor radiance measurements

Improved snow property retrievals by solving for topography in the inversion of at-sensor radiance measurements Brenton A. Wilder, Joachim Meyer, Josh Enterkine, and Nancy F. Glenn The Cryosphere, 18, 5015–5029, https://doi.org/10.5194/tc-18-5015-2024, 2024 Remotely sensed properties of snow are dependent on accurate terrain information, which for a lot of the cryosphere and seasonal snow zones is often insufficient in accuracy. However, as we show in this paper, we can bypass this issue by optimally solving for the terrain by utilizing the raw radiance data returned to the sensor. This method performed well when compared to validation datasets and has the potential to be used across a variety of different snow climates.

Blood test could help diagnose bipolar disorder — but some researchers are sceptical

Nature, Published online: 06 November 2024; doi:10.1038/d41586-024-03616-7

Observation of vortices in a dipolar supersolid

Nature, Published online: 06 November 2024; doi:10.1038/s41586-024-08149-7

Sea angels and devils: could plankton unlock the secrets of human biology?

Scientists use new technology to sequence the DNA of microscopic ocean creatures for the first time

Off the west coast of Greenland, a 17-metre (56ft) aluminium sailing boat creeps through a narrow, rocky fjord in the Arctic twilight. The research team onboard, still bleary-eyed from the rough nine-day passage across the Labrador Sea, lower nets to collect plankton. This is the first time anyone has sequenced the DNA of the tiny marine creatures that live here.

Watching the nets with palpable excitement is Prof Leonid Moroz, a neuroscientist at the University of Florida’s Whitney marine lab. “This is what the world looked like when life began,” he tells his friend, Peter Molnar, the expedition leader with whom he co-founded the Ocean Genome Atlas Project (Ogap).

A simple snow temperature index model exposes discrepancies between reanalysis snow water equivalent products

A simple snow temperature index model exposes discrepancies between reanalysis snow water equivalent products Aleksandra Elias Chereque, Paul J. Kushner, Lawrence Mudryk, Chris Derksen, and Colleen Mortimer The Cryosphere, 18, 4955–4969, https://doi.org/10.5194/tc-18-4955-2024, 2024 We look at three commonly used snow depth datasets that are produced through a combination of snow modelling and historical measurements (reanalysis). When compared with each other, these datasets have differences that arise for various reasons. We show that a simple snow model can be used to examine these inconsistencies and highlight issues. This method indicates that one of the complex datasets should be excluded from further studies.

Contribution of blowing-snow sublimation to the surface mass balance of Antarctica

Contribution of blowing-snow sublimation to the surface mass balance of Antarctica Srinidhi Gadde and Willem Jan van de Berg The Cryosphere, 18, 4933–4953, https://doi.org/10.5194/tc-18-4933-2024, 2024 Blowing-snow sublimation is the major loss term in the mass balance of Antarctica. In this study we update the blowing-snow representation in the Regional Atmospheric Climate Model (RACMO). With the updates, results compare well with observations from East Antarctica. Also, the continent-wide variation of blowing snow compares well with satellite observations. Hence, the updates provide a clear step forward in producing a physically sound and reliable estimate of the mass balance of Antarctica.

Hubble and Webb probe surprisingly smooth disk around Vega

In the 1997 movie "Contact," adapted from Carl Sagan's 1985 novel, the lead character scientist Ellie Arroway (played by actor Jodi Foster) takes a space-alien-built wormhole ride to the star Vega. She emerges inside a snowstorm of debris encircling the star—but no obvious planets are visible.

International SWOT satellite spots planet-rumbling Greenland tsunami

The international Surface Water and Ocean Topography (SWOT) satellite mission, a collaboration between NASA and France's CNES (Center National d'Études Spatiales), detected the unique contours of a tsunami that sloshed within the steep walls of a fjord in Greenland in September 2023.

Earth from Space: Ross Island, Antarctica

Image: The icy landscape of Ross Island in Antarctica is featured in this Copernicus Sentinel-2 image from 3 February 2024, during the austral summer.

Landmark 20-year study of climate change impact on permafrost forests

A research team conducted perhaps the first long-term observation of CO2 budget in a permafrost forest. During the 20 years from 2003-2022, the team uncovered intriguing findings in the interior of Alaska.

Large meltwater accumulation revealed inside Greenland Ice Sheet

A new study unveils a surprising discovery: a substantial amount of meltwater is temporarily stored within the Greenland Ice Sheet during summer months. For the first time, an international group of researchers was able to quantify meltwater with positioning data. The finding challenges current models of how ice sheets contribute to global sea level rise.

Vertical bedrock shifts reveal summer water storage in Greenland ice sheet

Nature, Published online: 30 October 2024; doi:10.1038/s41586-024-08096-3

Softening of the optical phonon by reduced interatomic bonding strength without depolarization

Nature, Published online: 30 October 2024; doi:10.1038/s41586-024-08099-0

New NASA instrument for studying snowpack completes airborne testing

Summer heat has significant effects in the mountainous regions of the western United States. Melted snow washes from snowy peaks into the rivers, reservoirs, and streams that supply millions of Americans with freshwater—as much as 75% of the annual freshwater supply for some states.

Weddell seals in the Antarctic strategically time their most extreme dives to maximize foraging

Weddell seals in Erebus Bay, Antarctica, may look like couch potatoes when they are resting on ice. However, these seals, which are the southernmost population of the southernmost living mammals, are exceptional divers that can reach depths of more than 900 meters and recorded dives lasting 96 minutes, which is well beyond their aerobic threshold. Scientists have identified an optimal and novel dive foraging strategy the seals employ to capture prey in the highly seasonal Antarctic environment with its rapidly changing light regimes. In this optimal foraging strategy, the seals typically strategically conduct their deepest, longest, most extreme dives earlier than solar noon, rather than during peak foraging times at midday. Extreme dives require seals to have longer recuperation times once they return to the surface, and so cuts into their foraging time. By conducting these dives early in the day, the seals can better take advantage of peak midday foraging times, according to the researchers.

Firn seismic anisotropy in the Northeast Greenland Ice Stream from ambient-noise surface waves

Firn seismic anisotropy in the Northeast Greenland Ice Stream from ambient-noise surface waves Emma Pearce, Dimitri Zigone, Coen Hofstede, Andreas Fichtner, Joachim Rimpot, Sune Olander Rasmussen, Johannes Freitag, and Olaf Eisen The Cryosphere, 18, 4917–4932, https://doi.org/10.5194/tc-18-4917-2024, 2024 Our study near EastGRIP camp in Greenland shows varying firn properties by direction (crucial for studying ice stream stability, structure, surface mass balance, and past climate conditions). We used dispersion curve analysis of Love and Rayleigh waves to show firn is nonuniform along and across the flow of an ice stream due to wind patterns, seasonal variability, and the proximity to the edge of the ice stream. This method better informs firn structure, advancing ice stream understanding.

Mount Fuji breaks records as it remains snowless for longer than ever before

Japan's highest mountain typically gets snow by early October, but there has been unusually warm weather this year.

How does a change in climate variability impact the Greenland ice sheet surface mass balance?

How does a change in climate variability impact the Greenland ice sheet surface mass balance? Tobias Zolles and Andreas Born The Cryosphere, 18, 4831–4844, https://doi.org/10.5194/tc-18-4831-2024, 2024 The Greenland ice sheet largely depends on the climate state. The uncertainties associated with the year-to-year variability have only a marginal impact on our simulated surface mass budget; this increases our confidence in projections and reconstructions. Basing the simulations on proxies, e.g., temperature, results in overestimates of the surface mass balance, as climatologies lead to small amounts of snowfall every day. This can be reduced by including sub-monthly precipitation variability.

The organization of subglacial drainage during the demise of the Finnish Lake District Ice Lobe

The organization of subglacial drainage during the demise of the Finnish Lake District Ice Lobe Adam J. Hepburn, Christine F. Dow, Antti Ojala, Joni Mäkinen, Elina Ahokangas, Jussi Hovikoski, Jukka-Pekka Palmu, and Kari Kajuutti The Cryosphere, 18, 4873–4916, https://doi.org/10.5194/tc-18-4873-2024, 2024 Terrain formerly occupied by ice sheets in the last ice age allows us to parameterize models of basal water flow using terrain and data unavailable beneath current ice sheets. Using GlaDS, a 2D basal hydrology model, we explore the origin of murtoos, a specific landform found throughout Finland that is thought to mark the upper limit of channels beneath the ice. Our results validate many of the predictions of murtoo origins and demonstrate that such models can be used to explore past ice sheets.

Characterizing southeast Greenland fjord surface ice and freshwater flux to support biological applications

Characterizing southeast Greenland fjord surface ice and freshwater flux to support biological applications Twila A. Moon, Benjamin Cohen, Taryn E. Black, Kristin L. Laidre, Harry L. Stern, and Ian Joughin The Cryosphere, 18, 4845–4872, https://doi.org/10.5194/tc-18-4845-2024, 2024 The complex geomorphology of southeast Greenland (SEG) creates dynamic fjord habitats for top marine predators, featuring glacier-derived floating ice, pack and landfast sea ice, and freshwater flux. We study the physical environment of SEG fjords, focusing on surface ice conditions, to provide a regional characterization that supports biological research. As Arctic warming persists, SEG may serve as a long-term refugium for ice-dependent wildlife due to the persistence of regional ice sheets.

Melting Arctic sea-ice could affect global ocean circulation

The warming climate in polar regions may significantly disrupt ocean circulation patterns, a new study indicates. Scientists discovered that in the distant past, growing inflows of freshwater from melting Arctic sea-ice into the Nordic Seas likely significantly affected ocean circulation, sending temperatures plummeting across northern Europe.

Slowing ocean current could ease Arctic warming -- a little

The Arctic is warming at three to four times the global average. However, new research suggests the slowing of a key ocean current could reduce projected Arctic warming by up to 2 degrees Celsius by the end of the century.

Polar bears and vampires? Building a new magnetometer home in Greenland

Throughout the summer of 2024 an intrepid team from DTU Space took to the Arctic climes of Narsarsuaq, Greenland, to install the latest in their portfolio of ground-based magnetometers and a snazzy all-sky camera to keep tabs on the changes in Earth’s magnetic field. Between icebergs and flower-filled valleys, fjords [...]

Waning snowfields have transformed into hotspots of greening within the alpine zone

Nature Climate Change, Published online: 25 October 2024; doi:10.1038/s41558-024-02177-x

Ice mélange melt changes observed water column stratification at a tidewater glacier in Greenland

Ice mélange melt changes observed water column stratification at a tidewater glacier in Greenland Nicole Abib, David A. Sutherland, Rachel Peterson, Ginny Catania, Jonathan D. Nash, Emily L. Shroyer, Leigh A. Stearns, and Timothy C. Bartholomaus The Cryosphere, 18, 4817–4829, https://doi.org/10.5194/tc-18-4817-2024, 2024 The melting of ice mélange, or dense packs of icebergs and sea ice in glacial fjords, can influence the water column by releasing cold fresh water deep under the ocean surface. However, direct observations of this process have remained elusive. We use measurements of ocean temperature, salinity, and velocity bookending an episodic ice mélange event to show that this meltwater input changes the density profile of a glacial fjord and has implications for understanding tidewater glacier change.

Russia’s Warming Arctic Is a Climate Threat. War Has Shut Scientists Out of It.

Climate science has been stymied as Russia continues its war in Ukraine. The stalled work threatens to leave the West without a clear picture of how fast the Earth is heating up.

Polar bears face higher risk of disease in a warming Arctic

Climate change and sea ice loss leaves polar bears exposed to more diseases, research suggests.

Brief communication: Stalagmite damage by cave ice flow quantitatively assessed by fluid–structure interaction simulations

Brief communication: Stalagmite damage by cave ice flow quantitatively assessed by fluid–structure interaction simulations Alexander H. Jarosch, Paul Hofer, and Christoph Spötl The Cryosphere, 18, 4811–4816, https://doi.org/10.5194/tc-18-4811-2024, 2024 Mechanical damage to stalagmites is commonly observed in mid-latitude caves. In this study we investigate ice flow along the cave bed as a possible mechanism for stalagmite damage. Utilizing models which simulate forces created by ice flow, we study the structural integrity of different stalagmite geometries. Our results suggest that structural failure of stalagmites caused by ice flow is possible, albeit unlikely.

Review article: Retrogressive thaw slump characteristics and terminology

Review article: Retrogressive thaw slump characteristics and terminology Nina Nesterova, Marina Leibman, Alexander Kizyakov, Hugues Lantuit, Ilya Tarasevich, Ingmar Nitze, Alexandra Veremeeva, and Guido Grosse The Cryosphere, 18, 4787–4810, https://doi.org/10.5194/tc-18-4787-2024, 2024 Retrogressive thaw slumps (RTSs) are widespread in the Arctic permafrost landforms. RTSs present a big interest for researchers because of their expansion due to climate change. There are currently different scientific schools and terminology used in the literature on this topic. We have critically reviewed existing concepts and terminology and provided clarifications to present a useful base for experts in the field and ease the introduction to the topic for scientists who are new to it.

Polar bears' exposure to pathogens is increasing as their environment changes

As the Arctic warms, polar bears now face a greater risk of contracting several pathogens than bears three decades ago, according to a new study.

Publisher Correction: Using both faces of polar semiconductor wafers for functional devices

Nature, Published online: 23 October 2024; doi:10.1038/s41586-024-08199-x

Elucidation of spatiotemporal structures from high-resolution blowing-snow observations

Elucidation of spatiotemporal structures from high-resolution blowing-snow observations Kouichi Nishimura, Masaki Nemoto, Yoichi Ito, Satoru Omiya, Kou Shimoyama, and Hirofumi Niiya The Cryosphere, 18, 4775–4786, https://doi.org/10.5194/tc-18-4775-2024, 2024 It is crucial to consider organized structures such as turbulence sweeps and ejections when discussing the onset and development of snow transport. This study aims to systematically measure blowing and drifting snow to investigate their spatiotemporal structures. To achieve this goal, we have deployed 15 snow particle counters (SPCs) in designated test areas and are conducting measurements using an equal number of ultrasonic anemometers, providing high-temporal-resolution data.

Change in grounding line location on the Antarctic Peninsula measured using a tidal motion offset correlation method

Change in grounding line location on the Antarctic Peninsula measured using a tidal motion offset correlation method Benjamin J. Wallis, Anna E. Hogg, Yikai Zhu, and Andrew Hooper The Cryosphere, 18, 4723–4742, https://doi.org/10.5194/tc-18-4723-2024, 2024 The grounding line, where ice begins to float, is an essential variable to understand ice dynamics, but in some locations it can be challenging to measure with established techniques. Using satellite data and a new method, Wallis et al. measure the grounding line position of glaciers and ice shelves in the Antarctic Peninsula and find retreats of up to 16.3 km have occurred since the last time measurements were made in the 1990s.

The cryostratigraphy of thermo-erosion gullies in the Canadian High Arctic demonstrates the resilience of permafrost

The cryostratigraphy of thermo-erosion gullies in the Canadian High Arctic demonstrates the resilience of permafrost Samuel Gagnon, Daniel Fortier, Étienne Godin, and Audrey Veillette The Cryosphere, 18, 4743–4763, https://doi.org/10.5194/tc-18-4743-2024, 2024 Thermo-erosion gullies (TEGs) are one of the most common forms of abrupt permafrost degradation. While their inception has been examined in several studies, the processes of their stabilization remain poorly documented. For this study, we investigated two TEGs in the Canadian High Arctic. We found that, while the formation of a TEG leaves permanent geomorphological scars in landscapes, in the long term, permafrost can recover to conditions similar to those pre-dating the initial disturbance.

Three-dimensional discrete element simulations on pressure ridge formation

Three-dimensional discrete element simulations on pressure ridge formation Marek Muchow and Arttu Polojärvi The Cryosphere, 18, 4765–4774, https://doi.org/10.5194/tc-18-4765-2024, 2024 We present the first explicit three-dimensional simulations of sea-ice ridge formation, which enables us to observe failure in several locations simultaneously. Sea-ice ridges are formed when ice converges and fails due to wind and ocean currents, so broken ice accumulates in a ridge. Previous two-dimensional models could not capture this behavior. We conclude that non-simultaneous failure is necessary to simulate ridging forces to assess how ridging forces relate to other ice properties.

Imaging X-ray Polarimetry Explorer helps researchers determine shape of black hole corona

New findings using data from NASA's IXPE (Imaging X-ray Polarimetry Explorer) mission offer unprecedented insight into the shape and nature of a structure important to black holes called a corona. The findings are published in The Astrophysical Journal.

Land cover succession for recently drained lakes in permafrost on the Yamal Peninsula, Western Siberia

Land cover succession for recently drained lakes in permafrost on the Yamal Peninsula, Western Siberia Clemens von Baeckmann, Annett Bartsch, Helena Bergstedt, Aleksandra Efimova, Barbara Widhalm, Dorothee Ehrich, Timo Kumpula, Alexander Sokolov, and Svetlana Abdulmanova The Cryosphere, 18, 4703–4722, https://doi.org/10.5194/tc-18-4703-2024, 2024 Lakes are common features in Arctic permafrost areas. Land cover change following their drainage needs to be monitored since it has implications for ecology and the carbon cycle. Satellite data are key in this context. We compared a common vegetation index approach with a novel land-cover-monitoring scheme. Land cover information provides specific information on wetland features. We also showed that the bioclimatic gradients play a significant role after drainage within the first 10 years.

Parachutes Made of Mucus Change How Some Scientists See the Ocean

With a new kind of microscope, researchers got a different view of how marine snow falls to the seafloor.

Assessing the representation of Arctic sea ice and the marginal ice zone in ocean–sea ice reanalyses

Assessing the representation of Arctic sea ice and the marginal ice zone in ocean–sea ice reanalyses Francesco Cocetta, Lorenzo Zampieri, Julia Selivanova, and Doroteaciro Iovino The Cryosphere, 18, 4687–4702, https://doi.org/10.5194/tc-18-4687-2024, 2024 Arctic sea ice is thinning and retreating because of global warming. Thus, the region is transitioning to a new state featuring an expansion of the marginal ice zone, a region where mobile ice interacts with waves from the open ocean. By analyzing 30 years of sea ice reconstructions that combine numerical models and observations, this paper proves that an ensemble of global ocean and sea ice reanalyses is an adequate tool for investigating the changing Arctic sea ice cover.

Contract secures build for ESA’s Harmony mission

ESA has awarded a contract valued at over €280 million to OHB in Germany to build ESA’s two Harmony Earth Explorer satellites.

This innovative research mission will provide valuable new data on various Earth processes, from shifts in the shape of the land surface caused by earthquakes and volcanic activity to insights into glacier movement. Additionally, it will enhance our understanding of the interactions between the upper ocean and lower atmosphere, all of which will contribute to a deeper comprehension of Earth's dynamic systems.

Simulated mission to Mars: Survey of lichen species

A collection-based survey of lichen species at the Mars Desert Research Station in Utah, USA and Flashline Mars Arctic Research Station in Nunavut, Canada was conducted as part of the Mars-160 mission, a simulation of Martian surface exploration. The survey identified 48 lichen taxa, with 35 species from the Utah site and 13 species from the Canadian site.

House science panel says an ‘absent’ NSF failed to protect Antarctic workers from sexual harassment

Report urges U.S. research agency to make safety a higher priority in new support contract

Centennial-scale variations in the carbon cycle enhanced by high obliquity

Nature Geoscience, Published online: 11 October 2024; doi:10.1038/s41561-024-01556-5

Declines in plant resilience threaten carbon storage in the Arctic

Rapid warming has impacted the northern ecosystem so significantly that scientists are concerned the region's vegetation is losing the ability to recover from climate shocks, suggests a new study.

Snowflake dance analysis could improve rain forecasts

Research observing the physical motion of falling ice crystals could help scientists better estimate where and when these crystals will melt into raindrops.

The grain-scale signature of isotopic diffusion in ice

The grain-scale signature of isotopic diffusion in ice Felix S. L. Ng The Cryosphere, 18, 4645–4669, https://doi.org/10.5194/tc-18-4645-2024, 2024 Liquid veins and grain boundaries in ice can accelerate the decay of climate signals in δ18O and δD by short-circuiting the slow isotopic diffusion in crystal grains. This theory for "excess diffusion" has not been confirmed experimentally. We show that, if the mechanism occurs, then distinct isotopic patterns must form near grain junctions, offering a testable prediction of the theory. We calculate the patterns and describe an experimental scheme for testing ice-core samples for the mechanism.

Exploring the decision-making process in model development: focus on the Arctic snowpack

Exploring the decision-making process in model development: focus on the Arctic snowpack Cecile B. Menard, Sirpa Rasmus, Ioanna Merkouriadi, Gianpaolo Balsamo, Annett Bartsch, Chris Derksen, Florent Domine, Marie Dumont, Dorothee Ehrich, Richard Essery, Bruce C. Forbes, Gerhard Krinner, David Lawrence, Glen Liston, Heidrun Matthes, Nick Rutter, Melody Sandells, Martin Schneebeli, and Sari Stark The Cryosphere, 18, 4671–4686, https://doi.org/10.5194/tc-18-4671-2024, 2024 Computer models, like those used in climate change studies, are written by modellers who have to decide how best to construct the models in order to satisfy the purpose they serve. Using snow modelling as an example, we examine the process behind the decisions to understand what motivates or limits modellers in their decision-making. We find that the context in which research is undertaken is often more crucial than scientific limitations. We argue for more transparency in our research practice.

Simulating lake ice phenology using a coupled atmosphere–lake model at Nam Co, a typical deep alpine lake on the Tibetan Plateau

Simulating lake ice phenology using a coupled atmosphere–lake model at Nam Co, a typical deep alpine lake on the Tibetan Plateau Xu Zhou, Binbin Wang, Xiaogang Ma, Zhu La, and Kun Yang The Cryosphere, 18, 4589–4605, https://doi.org/10.5194/tc-18-4589-2024, 2024 The simulation of the ice phenology of Nam Co by WRF is investigated. Compared with the default model, improving the key lake schemes, such as water surface roughness length for heat fluxes and the shortwave radiation transfer for lake ice, can better simulate the lake ice phenology. The still existing errors in the spatial patterns of lake ice phenology imply that challenges still exist in modelling key lake and non-lake physics such as grid-scale water circulation and snow-related processes.

El Niño enhances snow-line rise and ice loss on the Quelccaya Ice Cap, Peru

El Niño enhances snow-line rise and ice loss on the Quelccaya Ice Cap, Peru Kara A. Lamantia, Laura J. Larocca, Lonnie G. Thompson, and Bryan G. Mark The Cryosphere, 18, 4633–4644, https://doi.org/10.5194/tc-18-4633-2024, 2024 Glaciers that exist within tropical regions are vital water resources and excellent indicators of a changing climate. We use satellite imagery analysis to detect the boundary between snow and ice on the Quelccaya Ice Cap (QIC), Peru, which indicates the ice cap's overall health. These results are analyzed with other variables, such as temperature, precipitation, and sea surface temperature anomalies, to better understand the factors and timelines driving the ice retreat.

Exploring the potential of forest snow modeling at the tree and snowpack layer scale

Exploring the potential of forest snow modeling at the tree and snowpack layer scale Giulia Mazzotti, Jari-Pekka Nousu, Vincent Vionnet, Tobias Jonas, Rafife Nheili, and Matthieu Lafaysse The Cryosphere, 18, 4607–4632, https://doi.org/10.5194/tc-18-4607-2024, 2024 As many boreal and alpine forests have seasonal snow, models are needed to predict forest snow under future environmental conditions. We have created a new forest snow model by combining existing, very detailed model components for the canopy and the snowpack. We applied it to forests in Switzerland and Finland and showed how complex forest cover leads to a snowpack layering that is very variable in space and time because different processes prevail at different locations in the forest.

My pilgrimage to the vanishing Sphinx snow patch

The Sphinx, a patch of snow thought to be the longest-lasting in the UK, has melted for the fourth consecutive year.

Melt sensitivity of irreversible retreat of Pine Island Glacier

Melt sensitivity of irreversible retreat of Pine Island Glacier Brad Reed, J. A. Mattias Green, Adrian Jenkins, and G. Hilmar Gudmundsson The Cryosphere, 18, 4567–4587, https://doi.org/10.5194/tc-18-4567-2024, 2024 We use a numerical ice-flow model to simulate the response of a 1940s Pine Island Glacier to changes in melting beneath its ice shelf. A decadal period of warm forcing is sufficient to push the glacier into an unstable, irreversible retreat from its long-term position on a subglacial ridge to an upstream ice plain. This retreat can only be stopped when unrealistic cold forcing is applied. These results show that short warm anomalies can lead to quick and substantial increases in ice flux.

2024 Antarctic sea ice maximum extent finishes at second lowest

On September 19, Antarctic sea ice likely reached its annual maximum extent of 17.16 million square kilometers (6.63 million square miles). The 2024 maximum is the second lowest in the 46-year satellite record above only 2023.

The new abnormal

Since 2007, the Arctic sea ice minimum has dropped below 5 million square kilometers (1.93 million square miles) every year, except in 2009, 2013, and 2014, when extent barely crossed the 5 million square kilometer mark. Such low extents would have been hard to imagine in the 1990s, when extent averaged 6.46 million square kilometers (2.49 million square miles). Arctic climate warming continues to lead an unfortunate path of change for the planet. Here, NSIDC researchers summarize this year’s events in the Arctic, and touch upon Antarctica sea ice extent at the end of its austral winter.

Modelling the effect of free convection on permafrost melting rates in frozen rock clefts

Modelling the effect of free convection on permafrost melting rates in frozen rock clefts Amir Sedaghatkish, Frédéric Doumenc, Pierre-Yves Jeannin, and Marc Luetscher The Cryosphere, 18, 4531–4546, https://doi.org/10.5194/tc-18-4531-2024, 2024 We developed a model to simulate the natural convection of water within frozen rock crevices subject to daily warming in mountain permafrost regions. Traditional models relying on conduction and latent heat flux typically overlook free convection. The results reveal that free convection can significantly accelerate the melting rate by an order of magnitude compared to conduction-based models. Our results are important for assessing the impact of climate change on mountain infrastructure.

A model framework for atmosphere–snow water vapor exchange and the associated isotope effects at Dome Argus, Antarctica – Part 1: The diurnal changes

A model framework for atmosphere–snow water vapor exchange and the associated isotope effects at Dome Argus, Antarctica – Part 1: The diurnal changes Tianming Ma, Zhuang Jiang, Minghu Ding, Pengzhen He, Yuansheng Li, Wenqian Zhang, and Lei Geng The Cryosphere, 18, 4547–4565, https://doi.org/10.5194/tc-18-4547-2024, 2024 We constructed a box model to evaluate the isotope effects of atmosphere–snow water vapor exchange at Dome A, Antarctica. The results show clear and invisible diurnal changes in surface snow isotopes under summer and winter conditions, respectively. The model also predicts that the annual net effects of atmosphere–snow water vapor exchange would be overall enrichments in snow isotopes since the effects in summer appear to be greater than those in winter at the study site.

The rate of climate change threatens to exceed the adaptive capacity of species

A recent study focusing on the Arctic Siberian primrose underscores the critical need to curb climate change to allow species time to adapt through evolution.

‘Ring of Fire’ Solar Eclipse Will Be Visible in Parts of South America

Not everyone will be able to see the phenomenon, known as an annular eclipse, on Wednesday, though a partial solar eclipse may be visible in parts of Antarctica and Hawaii.

From crevasse falls to polar bears, train fieldwork leaders for emergencies

Nature, Published online: 02 October 2024; doi:10.1038/d41586-024-03155-1

Unveiling the hidden snow dunes shaping Antarctica's frozen landscape

Sand dunes are a familiar sight along beaches and in deserts. While we know how regular sand dunes are formed, much less is known about dunes made of snow. In a new study, scientists have analysed the vast snow dunes across Antarctica – reshaping our understanding of the continent's surface dynamics.

This research sheds light on the unexplored world of Antarctic snow dunes, offering a fresh perspective on the complex interactions between wind, snow and climate in one of Earth's harshest environments.

Why the most climate-resistant glaciers are hiding in plain sight

In the American West, white glaciers and snow fields are outnumbered by long-overlooked “rock glaciers.” The rock covering these vast hunks of ice makes them far less affected by warming temperatures.

The Vikings were part of a global network trading in ivory from Greenland

New research shows that the Vikings traveled more than 6,000 kilometers to the Arctic to hunt for walrus. DNA analyses reveal that walrus ivory from Greenland was brought to Europe and probably as far as the Middle East [M1] via extensive trade networks.

Switzerland and Italy redraw border due to melting glaciers

Glacier ridgelines marking the border near the Matterhorn mountain are shifting as ice continues to melt.

Any ice-age telepaths out there? Please explain why Netflix is revisiting Ancient Apocalypse | Catherine Bennett

A catastrophe is indeed looming in letting Graham Hancock return with his oddball theories, now with Keanu Reeves in tow

Diary note: it may seem a while off, but the end of the world is still scheduled for 2030, precise date TBC. After once suggesting that nameless devastation could be upon us in 2012, the evergreen eschatologist Graham Hancock subsequently updated his advice to a comet, now six years off. Or thereabouts. MailOnline, which has been exhuming an ancient Hancock text, reminds readers of his “dire warning for our age”.

What is certain, anyway, is that a great and horrifying catastrophe will occur as soon as 16 October. This is the day Netflix will launch something astounding, almost beyond belief, something sceptics said could never happen: series 2 of Hancock’s Ancient Apocalypse. And stranger still: this terrible event stars, along with Hancock, the Hollywood actor Keanu Reeves.

Do you have an opinion on the issues raised in this article? If you would like to submit a letter of up to 250 words to be considered for publication, email it to us at observer.letters@observer.co.uk

Unprecedented 21st century glacier loss on Mt. Hood, Oregon, USA

Unprecedented 21st century glacier loss on Mt. Hood, Oregon, USA Nicolas Bakken-French, Stephen J. Boyer, B. Clay Southworth, Megan Thayne, Dylan H. Rood, and Anders E. Carlson The Cryosphere, 18, 4517–4530, https://doi.org/10.5194/tc-18-4517-2024, 2024 Repeat photography, field mapping, and remote sensing find that glaciers on Mt. Hood, Oregon, have lost about 25 % of their area in the first 2 decades of the 21st century and 17 % of their area in the last 7–8 years. The 21st century recession rate is more than 3 times faster than the 20th century average and 1.9 times faster than the fastest period of retreat within the 20th century. This unprecedented retreat corresponds to regional summer warming of 1.7–1.8°C relative to the early 1900s.

From Open Water at the North Pole, to a Marathon Run on an Ice Floe, It Was Quite an Arctic Summer

The extent of Arctic sea ice has shriveled to its lowest extent for the year, heralding the end of summer. The ice covers about 750,000 fewer square miles of ocean than average — a testament to continuing climate change.

A study found Facebook’s algorithm didn’t promote political polarization. Critics have doubts

Letter to Science questions experiment done during 2020 U.S. elections

Identifying airborne snow metamorphism with stable water isotopes

Identifying airborne snow metamorphism with stable water isotopes Sonja Wahl, Benjamin Walter, Franziska Aemisegger, Luca Bianchi, and Michael Lehning The Cryosphere, 18, 4493–4515, https://doi.org/10.5194/tc-18-4493-2024, 2024 Wind-driven airborne transport of snow is a frequent phenomenon in snow-covered regions and a process difficult to study in the field as it is unfolding over large distances. Thus, we use a ring wind tunnel with infinite fetch positioned in a cold laboratory to study the evolution of the shape and size of airborne snow. With the help of stable water isotope analyses, we identify the hitherto unobserved process of airborne snow metamorphism that leads to snow particle rounding and growth.

Ice cores show pollution's impact on Arctic atmosphere

A new study on ice cores from Alaska and Greenland found that air pollution from the burning of fossil fuels reaches the remote Arctic in amounts large enough to alter its fundamental atmospheric chemistry. The researchers unexpectedly found pollution's footprint in levels of an airborne byproduct of marine phytoplankton activity, which plummeted as soon as widespread fossil fuel usage began in the industrial era. The findings illustrate the long reach of fossil fuel emissions.

The long-term sea-level commitment from Antarctica

The long-term sea-level commitment from Antarctica Ann Kristin Klose, Violaine Coulon, Frank Pattyn, and Ricarda Winkelmann The Cryosphere, 18, 4463–4492, https://doi.org/10.5194/tc-18-4463-2024, 2024 We systematically assess the long-term sea-level response from Antarctica to warming projected over the next centuries, using two ice-sheet models. We show that this committed Antarctic sea-level contribution is substantially higher than the transient sea-level change projected for the coming decades. A low-emission scenario already poses considerable risk of multi-meter sea-level increase over the next millennia, while additional East Antarctic ice loss unfolds under the high-emission pathway.

Using both faces of polar semiconductor wafers for functional devices

Nature, Published online: 25 September 2024; doi:10.1038/s41586-024-07983-z

Atmospheric blocking slows ocean-driven melting of Greenland's largest glacier tongue

Northeast Greenland is home to the 79 N Glacier -- the country's largest floating glacier tongue, but also one seriously threatened by global warming: warm water from the Atlantic is melting it from below. Experts have however now determined that the temperature of the water flowing into the glacier cavern declined from 2018 to 2021, even though the ocean has steadily warmed in the region over the past several decades. This could be due to temporarily changed atmospheric circulation patterns. Researchers now discuss how this affects the ocean and what it could mean for the future of Greenland's glaciers.

The influence of present-day regional surface mass balance uncertainties on the future evolution of the Antarctic Ice Sheet

The influence of present-day regional surface mass balance uncertainties on the future evolution of the Antarctic Ice Sheet Christian Wirths, Thomas F. Stocker, and Johannes C. R. Sutter The Cryosphere, 18, 4435–4462, https://doi.org/10.5194/tc-18-4435-2024, 2024 We investigated the influence of several regional climate models on the Antarctic Ice Sheet when applied as forcing for the Parallel Ice Sheet Model (PISM). Our study shows that the choice of regional climate model forcing results in uncertainties of around a tenth of those in future sea level rise projections and also affects the extent of grounding line retreat in West Antarctica.

Quantifying the influence of snow over sea ice morphology on L-band passive microwave satellite observations in the Southern Ocean

Quantifying the influence of snow over sea ice morphology on L-band passive microwave satellite observations in the Southern Ocean Lu Zhou, Julienne Stroeve, Vishnu Nandan, Rosemary Willatt, Shiming Xu, Weixin Zhu, Sahra Kacimi, Stefanie Arndt, and Zifan Yang The Cryosphere, 18, 4399–4434, https://doi.org/10.5194/tc-18-4399-2024, 2024 Snow over Antarctic sea ice, influenced by highly variable meteorological conditions and heavy snowfall, has a complex stratigraphy and profound impact on the microwave signature. We employ advanced radiation transfer models to analyse the effects of complex snow properties on brightness temperatures over the sea ice in the Southern Ocean. Great potential lies in the understanding of snow processes and the application to satellite retrievals.

Arctic sea ice extent levels off; 2024 minimum set

On September 11, Arctic sea ice likely reached its annual minimum extent of 4.28 million square kilometers (1.65 million square miles). The 2024 minimum is the seventh lowest in the nearly 46-year satellite record. The last 18 years, from 2007 to 2024, are the lowest 18 sea ice extents in the satellite record.

How many parameters are needed to represent polar sea ice surface patterns and heterogeneity?

How many parameters are needed to represent polar sea ice surface patterns and heterogeneity? Joseph Fogarty, Elie Bou-Zeid, Mitchell Bushuk, and Linette Boisvert The Cryosphere, 18, 4335–4354, https://doi.org/10.5194/tc-18-4335-2024, 2024 We hypothesize that using a broad set of surface characterization metrics for polar sea ice surfaces will lead to more accurate representations in general circulation models. However, the first step is to identify the minimum set of metrics required. We show via numerical simulations that sea ice surface patterns can play a crucial role in determining boundary layer structures. We then statistically analyze a set of high-resolution sea ice surface images to obtain this minimal set of parameters.

Combining traditional and novel techniques to increase our understanding of the lock-in depth of atmospheric gases in polar ice cores – results from the EastGRIP region

Combining traditional and novel techniques to increase our understanding of the lock-in depth of atmospheric gases in polar ice cores – results from the EastGRIP region Julien Westhoff, Johannes Freitag, Anaïs Orsi, Patricia Martinerie, Ilka Weikusat, Michael Dyonisius, Xavier Faïn, Kevin Fourteau, and Thomas Blunier The Cryosphere, 18, 4379–4397, https://doi.org/10.5194/tc-18-4379-2024, 2024 We study the EastGRIP area, Greenland, in detail with traditional and novel techniques. Due to the compaction of the ice, at a certain depth, atmospheric gases can no longer exchange, and the atmosphere is trapped in air bubbles in the ice. We find this depth by pumping air from a borehole, modeling, and using a new technique based on the optical appearance of the ice. Our results suggest that the close-off depth lies at around 58–61 m depth and more precisely at 58.3 m depth.

How well can satellite altimetry and firn models resolve Antarctic firn thickness variations?

How well can satellite altimetry and firn models resolve Antarctic firn thickness variations? Maria T. Kappelsberger, Martin Horwath, Eric Buchta, Matthias O. Willen, Ludwig Schröder, Sanne B. M. Veldhuijsen, Peter Kuipers Munneke, and Michiel R. van den Broeke The Cryosphere, 18, 4355–4378, https://doi.org/10.5194/tc-18-4355-2024, 2024 The interannual variations in the height of the Antarctic Ice Sheet (AIS) are mainly due to natural variations in snowfall. Precise knowledge of these variations is important for the detection of any long-term climatic trends in AIS surface elevation. We present a new product that spatially resolves these height variations over the period 1992–2017. The product combines the strengths of atmospheric modeling results and satellite altimetry measurements.

Extreme polar light environment of the North and South Poles sustains biodiversity

Researchers working in Finland propose that the unique light environment of the Earth's Polar regions creates conditions that result in circumpolar hybrid zones around the North and the South Poles. These extreme conditions increase the synchrony of reproductive phenology among species, i.e., force all species into a smaller window for reproduction. This will sustain biodiversity in the long term.

Seasonal snow–atmosphere modeling: let's do it

Seasonal snow–atmosphere modeling: let's do it Dylan Reynolds, Louis Quéno, Michael Lehning, Mahdi Jafari, Justine Berg, Tobias Jonas, Michael Haugeneder, and Rebecca Mott The Cryosphere, 18, 4315–4333, https://doi.org/10.5194/tc-18-4315-2024, 2024 Information about atmospheric variables is needed to produce simulations of mountain snowpacks. We present a model that can represent processes that shape mountain snowpack, focusing on the accumulation of snow. Simulations show that this model can simulate the complex path that a snowflake takes towards the ground and that this leads to differences in the distribution of snow by the end of winter. Overall, this model shows promise with regard to improving forecasts of snow in mountains.

Multiscale modeling of heat and mass transfer in dry snow: influence of the condensation coefficient and comparison with experiments

Multiscale modeling of heat and mass transfer in dry snow: influence of the condensation coefficient and comparison with experiments Lisa Bouvet, Neige Calonne, Frédéric Flin, and Christian Geindreau The Cryosphere, 18, 4285–4313, https://doi.org/10.5194/tc-18-4285-2024, 2024 Four different macroscopic heat and mass transfer models have been derived for a large range of condensation coefficient values by an upscaling method. A comprehensive evaluation of the models is presented based on experimental datasets and numerical examples. The models reproduce the trend of experimental temperature and density profiles but underestimate the magnitude of the processes. Possible causes of these discrepancies and potential improvements for the models are suggested.

Feedback mechanisms controlling Antarctic glacial-cycle dynamics simulated with a coupled ice sheet–solid Earth model

Feedback mechanisms controlling Antarctic glacial-cycle dynamics simulated with a coupled ice sheet–solid Earth model Torsten Albrecht, Meike Bagge, and Volker Klemann The Cryosphere, 18, 4233–4255, https://doi.org/10.5194/tc-18-4233-2024, 2024 We performed coupled ice sheet–solid Earth simulations and discovered a positive (forebulge) feedback mechanism for advancing grounding lines, supporting a larger West Antarctic Ice Sheet during the Last Glacial Maximum. During deglaciation we found that the stabilizing glacial isostatic adjustment feedback dominates grounding-line retreat in the Ross Sea, with a weak Earth structure. This may have consequences for present and future ice sheet stability and potential rates of sea-level rise.

Antarctic sensitivity to oceanic melting parameterizations

Antarctic sensitivity to oceanic melting parameterizations Antonio Juarez-Martinez, Javier Blasco, Alexander Robinson, Marisa Montoya, and Jorge Alvarez-Solas The Cryosphere, 18, 4257–4283, https://doi.org/10.5194/tc-18-4257-2024, 2024 We present sea level projections for Antarctica in the context of ISMIP6-2300 with several forcings but extend the simulations to 2500, showing that more than 3 m of sea level contribution could be reached. We also test the sensitivity on a basal melting parameter and determine the timing of the loss of ice in the west region. All the simulations were carried out with the ice sheet model Yelmo.

Arctic warming may fuel ice formation in clouds

Rising temperatures are thought to reduce the number of ice crystals in clouds, leading to the formation of liquid-dominated clouds. However, a new study has found that Arctic warming is causing an increase in the emission of natural aerosols from snow/ice-free barren and vegetated areas in the Arctic. These aerosols can encourage ice crystal formation in mixed-phase clouds, potentially affecting cloud composition and the Arctic climate.

Arctic Weather Satellite’s first images capture Storm Boris

Just a month after its launch, ESA’s Arctic Weather Satellite has already delivered its first images, notably capturing Storm Boris, which has been wreaking havoc across central Europe. 

Measurements of frazil ice flocs in rivers

Measurements of frazil ice flocs in rivers Chuankang Pei, Jiaqi Yang, Yuntong She, and Mark Loewen The Cryosphere, 18, 4177–4196, https://doi.org/10.5194/tc-18-4177-2024, 2024 Frazil flocs are aggregates of frazil ice particles that form in supercooled water. As they grow, they rise to the river surface, contributing to ice cover formation. We measured the properties of frazil flocs in rivers for the first time using underwater imaging. We found that the floc size distributions follow a lognormal distribution and mean floc size decreases linearly as the local Reynolds number increases. Floc volume concentration has a power law correlation with the relative depth.

Employing automated electrical resistivity tomography for detecting short- and long-term changes in permafrost and active-layer dynamics in the maritime Antarctic

Employing automated electrical resistivity tomography for detecting short- and long-term changes in permafrost and active-layer dynamics in the maritime Antarctic Mohammad Farzamian, Teddi Herring, Gonçalo Vieira, Miguel Angel de Pablo, Borhan Yaghoobi Tabar, and Christian Hauck The Cryosphere, 18, 4197–4213, https://doi.org/10.5194/tc-18-4197-2024, 2024 An automated electrical resistivity tomography (A-ERT) system was developed and deployed in Antarctica to monitor permafrost and active-layer dynamics. The A-ERT, coupled with an efficient processing workflow, demonstrated its capability to monitor real-time thaw depth progression, detect seasonal and surficial freezing–thawing events, and assess permafrost stability. Our study showcased the potential of A-ERT to contribute to global permafrost monitoring networks.

Analytical solutions for the advective–diffusive ice column in the presence of strain heating

Analytical solutions for the advective–diffusive ice column in the presence of strain heating Daniel Moreno-Parada, Alexander Robinson, Marisa Montoya, and Jorge Alvarez-Solas The Cryosphere, 18, 4215–4232, https://doi.org/10.5194/tc-18-4215-2024, 2024 Our study tries to understand how the ice temperature evolves in a large mass as in the case of Antarctica. We found a relation that tells us the ice temperature at any point. These results are important because they also determine how the ice moves. In general, ice moves due to slow deformation (as if pouring honey from a jar). Nevertheless, in some regions the ice base warms enough and melts. The liquid water then serves as lubricant and the ice slides and its velocity increases rapidly.

The effect of ice shelf rheology on shelf edge bending

The effect of ice shelf rheology on shelf edge bending W. Roger Buck The Cryosphere, 18, 4165–4176, https://doi.org/10.5194/tc-18-4165-2024, 2024 Standard theory predicts that the edge of an ice shelf should bend downward. Satellite observations show that the edges of many ice shelves bend upward. A new theory for ice shelf bending is developed that, for the first time, includes the kind of vertical variations in ice flow properties expected for ice shelves. Upward bending of shelf edges is predicted as long as the ice surface is very cold and the ice flow properties depend strongly on temperature.

Arctic ecosystems get long-term look with drifting research station

Riding on top of sea ice, domed vessel will carry crews on 2-year-long polar voyages

A megatsunami in a remote fjord rang Earth like a bell for 9 days

Scientists trace strange seismic signal to landslide that triggered sloshing, 200-meter-tall waves in Greenland

New discovery about ice layer formation in ice sheets can improve sea level rise predictions

A newly discovered mechanism for the flow and freezing of ice sheet meltwater could improve estimates of sea level rise around the globe. Researchers have found a new mechanism that explains the process of how impermeable horizontal ice layers are formed below the surface, a process critical for determining the contribution of ice sheet meltwater to sea level rise.

Climate-change-triggered 2023 mega-landslide caused Earth to vibrate for nine days

A landslide in a remote part of Greenland caused a 200 meter (650 foot) mega-tsunami that sloshed back and forth across a fjord for nine days, generating vibrations throughout Earth, according to a new study. The study concluded that this movement of water was the cause of a mysterious, global seismic signal that lasted for nine days and puzzled seismologists in September 2023.

Mike Robins obituary

My father, Mike Robins, who has died aged 86, was a physiologist and cancer biologist whose research focus was on the growth of cells. He wrote many academic papers and, with Benjamin King, revised the standard undergraduate book Cancer Biology (2006).

He also loved marine biology and, with diving friends and colleagues at the University of London Sub Aqua Club, contributed in the 1960s and 70s to early descriptions of the marine ecology of Swanage Bay in Dorset, the Scilly Isles and Lundy. His particular interest was marine hydroids and the ecology of Dead Man’s Fingers (Alcyoniums). During a summer diving season in Antarctica with the British Antarctic Survey in 1970 he found and named a new hydroid species – Monobrachium antarcticum.

SpaceX performs historic first spacewalk with Polaris Dawn crew

SpaceX pulled off its first spacewalk in the early hours of Thursday morning, in a historic first for a company.

SpaceX Polaris Dawn: all-civilian crew completes first privately funded spacewalk – as it happened

This live blog is now closed, you can read our report of the spacewalk here

My colleague points out that the elbows of the new SpaceX suit looks like a “tumble drier pipe”.

This will take about 8 minutes as they empty the cabin of air.

Polaris Dawn astronauts complete first commercial spacewalk

Billionaire Jared Isaacman and SpaceX’s Sarah Gillis exit capsule in slimmed-down spacesuits hundreds of miles up

Two astronauts have completed the first commercial spacewalk and tested slimmed-down spacesuits designed by SpaceX, in one of the boldest attempts yet to push the boundaries of privately funded spaceflight.

Hundreds of miles above Earth and orbiting at close to 30,000km/h (18,600mph), the billionaire Jared Isaacman, 41, who chartered the Polaris Dawn mission, exited the space capsule at 11.52am BST on Thursday.

'A perfect world': billionaire's helmet cam shows moment of first ever private spacewalk – video

The billionaire Jared Isaacman and his fellow crew members completed the first privately funded spacewalk as a livestream of the mission showed Isaacman manually opening the hatch to enter space. Upon seeing Earth, he said: 'Back at home we all have a lot of work to do but from here, the Earth sure looks like a perfect world'

• SpaceX Polaris Dawn live: all-civilian crew completes first privately funded spacewalk

Assessing sea ice microwave emissivity up to submillimeter waves from airborne and satellite observations

Assessing sea ice microwave emissivity up to submillimeter waves from airborne and satellite observations Nils Risse, Mario Mech, Catherine Prigent, Gunnar Spreen, and Susanne Crewell The Cryosphere, 18, 4137–4163, https://doi.org/10.5194/tc-18-4137-2024, 2024 Passive microwave observations from satellites are crucial for monitoring Arctic sea ice and atmosphere. To do this effectively, it is important to understand how sea ice emits microwaves. Through unique Arctic sea ice observations, we improved our understanding, identified four distinct emission types, and expanded current knowledge to include higher frequencies. These findings will enhance our ability to monitor the Arctic climate and provide valuable information for new satellite missions.

Modelling subglacial fluvial sediment transport with a graph-based model, Graphical Subglacial Sediment Transport (GraphSSeT)

Modelling subglacial fluvial sediment transport with a graph-based model, Graphical Subglacial Sediment Transport (GraphSSeT) Alan Robert Alexander Aitken, Ian Delaney, Guillaume Pirot, and Mauro A. Werder The Cryosphere, 18, 4111–4136, https://doi.org/10.5194/tc-18-4111-2024, 2024 Understanding how glaciers generate sediment and transport it to the ocean is important for understanding ocean ecosystems and developing knowledge of the past cryosphere from marine sediments. This paper presents a new way to simulate sediment transport in rivers below ice sheets and glaciers and quantify volumes and characteristics of sediment that can be used to reveal the hidden record of the subglacial environment for both past and present glacial conditions.

SpaceX Polaris Dawn astronauts conduct the first-ever private spacewalk

An internet entrepreneur and a SpaceX engineer have become the first private astronauts to walk in space.

SpaceX Polaris Dawn Spacewalk: How to Watch the Astronauts

The astronauts of the Polaris Dawn mission, after traveling through heavy radiation and high orbits, are getting ready to open the hatch of their SpaceX vehicle.

Weird signal that baffled seismologists traced to mega-landslide in Greenland

Nature, Published online: 12 September 2024; doi:10.1038/d41586-024-02969-3

First private spacewalk a success! What the SpaceX mission means for science

Nature, Published online: 12 September 2024; doi:10.1038/d41586-024-02855-y

9 phenomena NASA astronauts will encounter at Moon's south pole

NASA's Artemis campaign will send the first woman and the first person of color to the moon's south polar region, marking humanity's first return to the lunar surface in more than 50 years.

Polaris Dawn project aims to prevent bone loss in space

Dartmouth researchers have a project aboard the Polaris Dawn mission they hope will help address two major health risks of space flight—the breakdown of astronauts' bones in zero-gravity conditions and the resulting danger of developing kidney stones.

Antarctic research supports healthy space for astronauts

Astronauts and Australian Antarctic expeditioners are working together to advance human health in space, and on Earth.

SpaceX Polaris Dawn crew set for historic private spacewalk

After trekking deeper into space than any humans in the last half-century, a pioneering private crew is set to make history Thursday with the first-ever spacewalk by non-professional astronauts.

Polaris Dawn Astronauts in SpaceX Dragon Reach Record Orbit Above Earth

After launching early on Tuesday, the billionaire Jared Isaacman and his crew traveled to altitudes not visited by any astronaut since the Apollo moon missions of the 1960s and ’70s.

Technicality gives Raygun world number one ranking

The Australian breakdancer is on top of the latest rankings despite her polarizing Olympic routine.

Two-axis twisting using Floquet-engineered XYZ spin models with polar molecules

Nature, Published online: 11 September 2024; doi:10.1038/s41586-024-07883-2

Controllable p- and n-type behaviours in emissive perovskite semiconductors

Nature, Published online: 11 September 2024; doi:10.1038/s41586-024-07792-4

Which global reanalysis dataset has better representativeness in snow cover on the Tibetan Plateau?

Which global reanalysis dataset has better representativeness in snow cover on the Tibetan Plateau? Shirui Yan, Yang Chen, Yaliang Hou, Kexin Liu, Xuejing Li, Yuxuan Xing, Dongyou Wu, Jiecan Cui, Yue Zhou, Wei Pu, and Xin Wang The Cryosphere, 18, 4089–4109, https://doi.org/10.5194/tc-18-4089-2024, 2024 The snow cover over the Tibetan Plateau (TP) plays a role in climate and hydrological systems, yet there are uncertainties in snow cover fraction (SCF) estimations within reanalysis datasets. This study utilized the Snow Property Inversion from Remote Sensing (SPIReS) SCF data to assess the accuracy of eight widely used reanalysis SCF datasets over the TP. Factors contributing to uncertainties were analyzed, and a combined averaging method was employed to provide optimized SCF simulations.

SpaceX's Polaris Dawn mission blasts off

The expedition, funded by billionaire Jared Isaacman, will attempt the world's first private spacewalk.

Polaris Dawn mission blasts off with plans for first commercial spacewalk

Privately funded five-day mission by four astronauts led by US billionaire launches on SpaceX rocket from Florida

Four astronauts have blasted out of the atmosphere as part of a privately funded five-day mission that aims to carry out the first commercial spacewalk.

Jared Isaacman, the American billionaire founder of the electronic payment company Shift4, is bankrolling the Polaris Dawn mission and acting as commander of the crew.

The Polaris Dawn spacewalk is SpaceX’s ‘risky adventure’

New spacesuits, untested astronauts, and a lot that can go wrong make this five-day mission unusually complex, but with a potentially great reward.

SpaceX launches all-civilian crew for first private spacewalk

SpaceX launched its historic Polaris Dawn mission on Tuesday—an audacious orbital expedition that will catapult civilians into a high-radiation region of space and see them attempt the first-ever spacewalk by non-professional astronauts.

SpaceX’s Polaris Dawn Launch: What to Know and How to Watch

A private mission, scheduled to launch at 3:38 a.m. Eastern time Tuesday after a series of delays, would take people farther from Earth than anyone has traveled since the end of NASA’s Apollo moon missions.

Into the abyss beneath Greenland’s glaciers – podcast

Environment editor Damian Carrington tells Madeleine Finlay about his recent trip to Greenland on board a ship with a group of intrepid scientists. They were on a mission to explore the maelstrom beneath Greenland’s glaciers, an area that has never been studied before, and were hoping to find answers to one of the world’s most pressing questions – how quickly will sea levels rise?

‘Oh my God, what is that?’: how the maelstrom under Greenland’s glaciers could slow future sea level rise

First results of the polar regional climate model RACMO2.4

First results of the polar regional climate model RACMO2.4 Christiaan T. van Dalum, Willem Jan van de Berg, Srinidhi N. Gadde, Maurice van Tiggelen, Tijmen van der Drift, Erik van Meijgaard, Lambertus H. van Ulft, and Michiel R. van den Broeke The Cryosphere, 18, 4065–4088, https://doi.org/10.5194/tc-18-4065-2024, 2024 We present a new version of the polar Regional Atmospheric Climate Model (RACMO), version 2.4p1, and show first results for Greenland, Antarctica and the Arctic. We provide an overview of all changes and investigate the impact that they have on the climate of polar regions. By comparing the results with observations and the output from the previous model version, we show that the model performs well regarding the surface mass balance of the ice sheets and near-surface climate.

Space travel comes with risk—SpaceX's Polaris Dawn mission will push the envelope further than ever

Space is an unnatural environment for humans. We can't survive unprotected in a pure vacuum for more than two minutes. Getting to space involves being strapped to a barely contained chemical explosion.

On the importance to consider the cloud dependence in parameterizing the albedo of snow on sea ice

On the importance to consider the cloud dependence in parameterizing the albedo of snow on sea ice Lara Foth, Wolfgang Dorn, Annette Rinke, Evelyn Jäkel, and Hannah Niehaus The Cryosphere, 18, 4053–4064, https://doi.org/10.5194/tc-18-4053-2024, 2024 It is demonstrated that the explicit consideration of the cloud dependence of the snow surface albedo in a climate model results in a more realistic simulation of the surface albedo during the snowmelt period in late May and June. Although this improvement appears to be relatively insubstantial, it has significant impact on the simulated sea-ice volume and extent in the model due to an amplification of the snow/sea-ice albedo feedback, one of the main contributors to Arctic amplification.

Summer snow on Arctic sea ice modulated by the Arctic Oscillation

Nature Geoscience, Published online: 06 September 2024; doi:10.1038/s41561-024-01525-y

Scientific history, sampling approach, and physical characterization of the Camp Century subglacial material, a rare archive from beneath the Greenland Ice Sheet

Scientific history, sampling approach, and physical characterization of the Camp Century subglacial material, a rare archive from beneath the Greenland Ice Sheet Paul R. Bierman, Andrew J. Christ, Catherine M. Collins, Halley M. Mastro, Juliana Souza, Pierre-Henri Blard, Stefanie Brachfeld, Zoe R. Courville, Tammy M. Rittenour, Elizabeth K. Thomas, Jean-Louis Tison, and François Fripiat The Cryosphere, 18, 4029–4052, https://doi.org/10.5194/tc-18-4029-2024, 2024 In 1966, the U.S. Army drilled through the Greenland Ice Sheet at Camp Century, Greenland; they recovered 3.44 m of frozen material. Here, we decipher the material’s history. Water, flowing during a warm interglacial when the ice sheet melted from northwest Greenland, deposited the upper material which contains fossil plant and insect parts. The lower material, separated by more than a meter of ice with some sediment, is till, deposited by the ice sheet during a prior cold period. 

Hysteresis of idealized, instability-prone outlet glaciers in response to pinning-point buttressing variation

Hysteresis of idealized, instability-prone outlet glaciers in response to pinning-point buttressing variation Johannes Feldmann, Anders Levermann, and Ricarda Winkelmann The Cryosphere, 18, 4011–4028, https://doi.org/10.5194/tc-18-4011-2024, 2024 Here we show in simplified simulations that the (ir)reversibility of the retreat of instability-prone, Antarctica-type glaciers can strongly depend on the depth of the bed depression they rest on. If it is sufficiently deep, then the destabilized glacier does not recover from its collapsed state. Our results suggest that glaciers resting on a wide and deep bed depression, such as Antarctica's Thwaites Glacier, are particularly susceptible to irreversible retreat. 

Ice viscosity governs hydraulic fracture that causes rapid drainage of supraglacial lakes

Ice viscosity governs hydraulic fracture that causes rapid drainage of supraglacial lakes Tim Hageman, Jessica Mejía, Ravindra Duddu, and Emilio Martínez-Pañeda The Cryosphere, 18, 3991–4009, https://doi.org/10.5194/tc-18-3991-2024, 2024 Due to surface melting, meltwater lakes seasonally form on the surface of glaciers. These lakes drive hydrofractures that rapidly transfer water to the base of ice sheets. This paper presents a computational method to capture the complicated hydrofracturing process. Our work reveals that viscous ice rheology has a great influence on the short-term propagation of fractures, enabling fast lake drainage, whereas thermal effects (frictional heating, conduction, and freezing) have little influence.

How Earth's most intense heat wave ever impacted life in Antarctica

An atmospheric river brought warm, moist air to the coldest and driest corner of the planet in 2022, pushing temperatures 70 degrees above average. A new study reveals what happened to Antarctica's smallest animals.

Scientists uncover hidden source of snow melt: Dark brown carbon

Researchers have quantified the effect of dark brown carbon on snow melt.

Anti-whaling activist Paul Watson kept in Greenland jail

Japan has been seeking the arrest of Paul Watson over an incident in Antarctic waters in 2010.

Photosynthesis in near darkness

Photosynthesis can take place in nature even at extremely low light levels. This is the result of a study that investigated the development of Arctic microalgae at the end of the polar night. The study shows that photosynthesis in the ocean is possible under much lower light conditions, and can therefore take place at much greater depths, than previously assumed.

A better understanding of climate change: Researchers study cloud movement in the Arctic

Special features of the Arctic climate, such as the strong reflection of the sun's rays off the light snow or the low position of the sun, amplify global warming in the Arctic. However, researchers are often faced with the challenge of modelling the underlying climatic processes in order to be able to provide reliable weather forecasts. Scientists succeeded in precisely measuring the movement of air masses from and to the Arctic. This will contribute to a better understanding of the processes accelerating climate change in the region.

AWI-ICENet1: a convolutional neural network retracker for ice altimetry

AWI-ICENet1: a convolutional neural network retracker for ice altimetry Veit Helm, Alireza Dehghanpour, Ronny Hänsch, Erik Loebel, Martin Horwath, and Angelika Humbert The Cryosphere, 18, 3933–3970, https://doi.org/10.5194/tc-18-3933-2024, 2024 We present a new approach (AWI-ICENet1), based on a deep convolutional neural network, for analysing satellite radar altimeter measurements to accurately determine the surface height of ice sheets. Surface height estimates obtained with AWI-ICENet1 (along with related products, such as ice sheet height change and volume change) show improved and unbiased results compared to other products. This is important for the long-term monitoring of ice sheet mass loss and its impact on sea level rise.

Simulation of Arctic snow microwave emission in surface-sensitive atmosphere channels

Simulation of Arctic snow microwave emission in surface-sensitive atmosphere channels Melody Sandells, Nick Rutter, Kirsty Wivell, Richard Essery, Stuart Fox, Chawn Harlow, Ghislain Picard, Alexandre Roy, Alain Royer, and Peter Toose The Cryosphere, 18, 3971–3990, https://doi.org/10.5194/tc-18-3971-2024, 2024 Satellite microwave observations are used for weather forecasting. In Arctic regions this is complicated by natural emission from snow. By simulating airborne observations from in situ measurements of snow, this study shows how snow properties affect the signal within the atmosphere. Fresh snowfall between flights changed airborne measurements. Good knowledge of snow layering and structure can be used to account for the effects of snow and could unlock these data to improve forecasts.

Climate Change Is Making Glacier Tourism More Popular, and Riskier

More tourists are eager to visit vanishing glaciers and ice caves, but warming is also making the sites unstable.

Astronomers investigate the nature of a bright low-mass X-ray binary system

Using various space observatories, astronomers have performed X-ray polarimetric and spectral observations of a bright low-mass X-ray binary known as Serpens X-1. Results of the observational campaign, published August 29 on the preprint server arXiv, provide important insights into the nature of this system.

Why the next pandemic could come from the Arctic — and what to do about it

Nature, Published online: 04 September 2024; doi:10.1038/d41586-024-02830-7

The race to the bottom

With the waning of sunlight, the pace of sea ice loss in the Arctic is slowing, and the seasonal minimum is expected in mid-September. While a new record low is highly unlikely, extent at the beginning of September is below many recent years. Antarctic ice extent is approaching its seasonal maximum and is near last year's record low.

SpaceX Polaris Dawn mission set to launch early Friday

The SpaceX Polaris Dawn mission, a multiday orbital expedition set to feature the first-ever spacewalk by private citizens, is now scheduled to launch on Friday, according to the Federal Aviation Administration.

The Martian polar caps are not created equally—here's why

People have observed the bright Martian poles wax and wane for centuries, but only within the last 50 years have scientists discovered that they are mostly comprised of carbon dioxide cycling in and out of the atmosphere to the rhythm of the seasons. But exactly how this happens is a complex interplay of planetary processes that scientists are continually teasing out.

A decade (2008–2017) of water stable isotope composition of precipitation at Concordia Station, East Antarctica

A decade (2008–2017) of water stable isotope composition of precipitation at Concordia Station, East Antarctica Giuliano Dreossi, Mauro Masiol, Barbara Stenni, Daniele Zannoni, Claudio Scarchilli, Virginia Ciardini, Mathieu Casado, Amaëlle Landais, Martin Werner, Alexandre Cauquoin, Giampietro Casasanta, Massimo Del Guasta, Vittoria Posocco, and Carlo Barbante The Cryosphere, 18, 3911–3931, https://doi.org/10.5194/tc-18-3911-2024, 2024 Oxygen and hydrogen stable isotopes have been extensively used to reconstruct past temperatures, with precipitation representing the input signal of the isotopic records in ice cores. We present a 10-year record of stable isotopes in daily precipitation at Concordia Station: this is the longest record for inland Antarctica and represents a benchmark for quantifying post-depositional processes and improving the paleoclimate interpretation of ice cores.

FAA lets SpaceX get back to launches, but Polaris Dawn awaits good weather

SpaceX got the OK to fly again from the Federal Aviation Administration and didn't waste any time knocking out launches from both Florida and California early Saturday, but the crewed Polaris Dawn launch remains on hold because of weather.

Humans modulate the climate sensitivity of Arctic–boreal wildfires

Nature Geoscience, Published online: 02 September 2024; doi:10.1038/s41561-024-01522-1

Spatial variability in Arctic–boreal fire regimes influenced by environmental and human factors

Nature Geoscience, Published online: 02 September 2024; doi:10.1038/s41561-024-01505-2

New species of Antarctic dragonfish highlights its threatened ecosystem

A new species of Antarctic dragonfish, Akarotaxis gouldae or Banded Dragonfish, has been discovered in waters off the western Antarctic Peninsula. The species, named in honor of the recently decommissioned Antarctic research and supply vessel (ARSV) Laurence M. Gould and its crew, exemplifies both the unknown biodiversity and fragile state of the Antarctic ecosystem.

Mini lab secures NASA ride to the moon

A miniaturized laboratory developed by The Open University (OU) with support from RAL Space will fly to the lunar South Polar region in the European Space Agency's (ESA) Prospect package in search of volatiles, including water ice, as part of NASA's Commercial Lunar Payload Services initiative.

Polaris Dawn Mission to Earth’s Orbit Will Test SpaceX’s Capabilities

SpaceX’s Polaris Dawn mission aims to test newly designed spacesuits.

Monthly velocity and seasonal variations of the Mont Blanc glaciers derived from Sentinel-2 between 2016 and 2024

Monthly velocity and seasonal variations of the Mont Blanc glaciers derived from Sentinel-2 between 2016 and 2024 Fabrizio Troilo, Niccolò Dematteis, Francesco Zucca, Martin Funk, and Daniele Giordan The Cryosphere, 18, 3891–3909, https://doi.org/10.5194/tc-18-3891-2024, 2024 The study of glacier sliding along slopes is relevant in many aspects of glaciology. We processed Sentinel-2 satellite optical images of Mont Blanc, obtaining surface velocities of 30 glaciers between 2016 and 2024. The study revealed different behaviours and velocity variations that have relationships with glacier morphology. A velocity anomaly was observed in some glaciers of the southern side in 2020–2022, but its origin needs to be investigated further.

Layer-optimized synthetic aperture radar processing with a mobile phase-sensitive radar: a proof of concept for detecting the deep englacial stratigraphy of Colle Gnifetti, Switzerland and Italy

Layer-optimized synthetic aperture radar processing with a mobile phase-sensitive radar: a proof of concept for detecting the deep englacial stratigraphy of Colle Gnifetti, Switzerland and Italy Falk M. Oraschewski, Inka Koch, M. Reza Ershadi, Jonathan D. Hawkins, Olaf Eisen, and Reinhard Drews The Cryosphere, 18, 3875–3889, https://doi.org/10.5194/tc-18-3875-2024, 2024 Mountain glaciers have a layered structure which contains information about past snow accumulation and ice flow. Using ground-penetrating radar instruments, the internal structure can be observed. The detection of layers in the deeper parts of a glacier is often difficult. Here, we present a new approach for imaging the englacial structure of an Alpine glacier (Colle Gnifetti, Switzerland and Italy) using a phase-sensitive radar that can detect reflection depth changes at sub-wavelength scales.

Study reveals crucial role of mixing Atlantic and Arctic waters in global ocean circulation

A new study sheds light on the vital role that the mixing of Atlantic and Arctic waters plays in sustaining the Atlantic Meridional Overturning Circulation (AMOC), which is crucial for regulating Earth's climate.

Viral Genomes From Glaciers Reveal Earth’s Climate History

The researchers drilled into the Guliya Glacier to find these ancient genomes.

Sentinel-2C pre-launch media briefing

Video: 00:52:00

The Copernicus Sentinel-2C satellite is set for liftoff on 4 September on the last Vega rocket from Europe’s Spaceport in Kourou, French Guiana.

This recording is of a media briefing held on 29 August 2024 to offer journalists the possibility to learn more about the Sentinel-2 mission and the last flight of Vega, Europe’s nimble rocket specialising in launching small scientific and Earth observation spacecraft such as to sun-synchronous polar orbits, following the Sun.

The Sentinel-2 mission is based on a constellation of two identical satellites, Sentinel-2A and Sentinel-2B, flying in the same orbit but 180° apart to optimise coverage and revisit time. Once in orbit, Sentinel-2C will replace the Sentinel-2A unit – prolonging the life of the Sentinel-2 mission – ensuring a continuous supply of data for Copernicus, the Earth observation component of the EU Space Programme.

Data collected from Sentinel-2 are used for a wide range of applications, including precision farming, water quality monitoring, natural disaster management and methane emission detection.

Participants at the media briefing were:

• Simonetta Cheli, Director of Earth Observation Programmes, ESA 
• Toni Tolker-Nielsen, Director of Space Transportation, ESA 
• Stéphane Israël, CEO, Arianespace 
• Mauro Facchini, Head of Unit for Earth Observation, European Commission    

FAA grounds SpaceX ahead of historic Polaris Dawn commercial spacewalk

The Federal Aviation Administration opened the investigation after a rocket booster toppled aboard a drone ship after it was returning from lofting SpaceX's Starlink internet satellites into space.

SpaceX delays Polaris Dawn launch again with no new date set

Billionaire Jared Isaacman's return trip to space on the Polaris Dawn mission is having to wait a little longer after a launch pad issue forced one delay and now the weather has taken the next two launch opportunities off the board.

Retrieval of snow and soil properties for forward radiative transfer modeling of airborne Ku-band SAR to estimate snow water equivalent: the Trail Valley Creek 2018/19 snow experiment

Retrieval of snow and soil properties for forward radiative transfer modeling of airborne Ku-band SAR to estimate snow water equivalent: the Trail Valley Creek 2018/19 snow experiment Benoit Montpetit, Joshua King, Julien Meloche, Chris Derksen, Paul Siqueira, J. Max Adam, Peter Toose, Mike Brady, Anna Wendleder, Vincent Vionnet, and Nicolas R. Leroux The Cryosphere, 18, 3857–3874, https://doi.org/10.5194/tc-18-3857-2024, 2024 This paper validates the use of free open-source models to link distributed snow measurements to radar measurements in the Canadian Arctic. Using multiple radar sensors, we can decouple the soil from the snow contribution. We then retrieve the "microwave snow grain size" to characterize the interaction between the snow mass and the radar signal. This work supports future satellite mission development to retrieve snow mass information such as the future Canadian Terrestrial Snow Mass Mission.

Earth’s ambipolar electrostatic field and its role in ion escape to space

Nature, Published online: 28 August 2024; doi:10.1038/s41586-024-07480-3

Cold math, hot topic: Sea ice thermal conductivity

Researchers developed a mathematical model showing how brine movement in sea ice enhances heat transfer, potentially improving climate change predictions for polar regions.

Alaskan snow crab fishery, walloped by climate change, may never fully recover

After the valuable fishery’s dramatic collapse, a new analysis suggests an uncertain future

Researchers reveal the causes for Greenland's abnormal warming

The climate factors revealed in a new study shed light on Greenland's climate and can help predict the future development of Greenland's ice sheet.

Ice caps on Mars offer clues to ancient climates

As a first-year master's student in the Department of Earth Sciences, Katherine Lutz became fascinated by satellite images of Mars that showed spiraling shapes swirling across the planet's polar ice caps.

How dangerous is Polaris Dawn space walk from SpaceX Crew Dragon?

Billionaire Jared Isaacman could make history for all the right reasons during his Polaris Dawn mission when the hatch opens on a SpaceX Crew Dragon and he ventures out into the vacuum of space.

An analysis of the interaction between surface and basal crevasses in ice shelves

An analysis of the interaction between surface and basal crevasses in ice shelves Maryam Zarrinderakht, Christian Schoof, and Anthony Peirce The Cryosphere, 18, 3841–3856, https://doi.org/10.5194/tc-18-3841-2024, 2024 The objective of the study is to understand the interactions between surface and basal crevasses by conducting a stability analysis and addressing the implications of the findings for potential calving laws. The study's findings indicate that, while the propagation of one crack in the case of two aligned surface and basal crevasses does not significantly reinforce the propagation of the other, the presence of multiple crevasses on one side enhances stability and decreases crack propagation.

SpaceX Polaris Dawn launch pushed back after helium leak

SpaceX on Monday pushed back the historic launch of an all-civilian crew on an orbital expedition set to mark a new chapter in space exploration with the first spacewalk by private citizens.

Lake Tahoe sees first August snow in 20 years

The unseasonable weather comes months before the local ski season in the Sierra Nevada is due to start.

Addendum: Reduced Arctic Ocean CO₂ uptake due to coastal permafrost erosion

Nature Climate Change, Published online: 27 August 2024; doi:10.1038/s41558-024-02133-9

SpaceX Polaris Dawn Mission: Why a Billionaire Is Risking a Spacewalk

Jared Isaacman is leading three other privately trained astronauts on a SpaceX vehicle for Polaris Dawn, a mission that will include a daring spacewalk.

The role of atmospheric conditions in the Antarctic sea ice extent summer minima

The role of atmospheric conditions in the Antarctic sea ice extent summer minima Bianca Mezzina, Hugues Goosse, François Klein, Antoine Barthélemy, and François Massonnet The Cryosphere, 18, 3825–3839, https://doi.org/10.5194/tc-18-3825-2024, 2024 We analyze years with extraordinarily low sea ice extent in Antarctica during summer, until the striking record in 2022. We highlight common aspects among these events, such as the fact that the exceptional melting usually occurs in two key regions and that it is related to winds with a similar direction. We also investigate whether the summer conditions are preceded by an unusual state of the sea ice during the previous winter, as well as the physical processes involved.

'In the midnight sun, slaloming through icebergs' - brothers on perilous Arctic voyage

Isak and Alex Rockström face freezing waters and icebergs as they sail the perilous Northwest Passage.

Glacier-preserved Tibetan Plateau viral community probably linked to warm–cold climate variations

Nature Geoscience, Published online: 26 August 2024; doi:10.1038/s41561-024-01508-z

Two trapped after ice collapses in Iceland glacier

Two people in a tour group were also injured when ice collapsed in Breiðamerkurjökull glacier.

Microstructure-based modelling of snow mechanics: experimental evaluation of the cone penetration test

Microstructure-based modelling of snow mechanics: experimental evaluation of the cone penetration test Clémence Herny, Pascal Hagenmuller, Guillaume Chambon, Isabel Peinke, and Jacques Roulle The Cryosphere, 18, 3787–3805, https://doi.org/10.5194/tc-18-3787-2024, 2024 This paper presents the evaluation of a numerical discrete element method (DEM) by simulating cone penetration tests in different snow samples. The DEM model demonstrated a good ability to reproduce the measured mechanical behaviour of the snow, namely the force evolution on the cone and the grain displacement field. Systematic sensitivity tests showed that the mechanical response depends not only on the microstructure of the sample but also on the mechanical parameters of grain contacts.

Interactive snow avalanche segmentation from webcam imagery: results, potential, and limitations

Interactive snow avalanche segmentation from webcam imagery: results, potential, and limitations Elisabeth D. Hafner, Theodora Kontogianni, Rodrigo Caye Daudt, Lucien Oberson, Jan Dirk Wegner, Konrad Schindler, and Yves Bühler The Cryosphere, 18, 3807–3823, https://doi.org/10.5194/tc-18-3807-2024, 2024 For many safety-related applications such as road management, well-documented avalanches are important. To enlarge the information, webcams may be used. We propose supporting the mapping of avalanches from webcams with a machine learning model that interactively works together with the human. Relying on that model, there is a 90% saving of time compared to the "traditional" mapping. This gives a better base for safety-critical decisions and planning in avalanche-prone mountain regions.

Widespread longitudinal snow dunes in Antarctica shaped by sintering

Nature Geoscience, Published online: 23 August 2024; doi:10.1038/s41561-024-01506-1

Introducing Sea Ice Today

The National Snow and Ice Data Center (NSIDC) has launched an upgraded and streamlined Sea Ice Today website. The new site replaces the Arctic Sea Ice News & Analysis (ASINA) website but continues the NASA-funded work on near-real-time assessments, daily data images, and monthly analyses on sea ice conditions that began in 2007.

Megatsunami risk on the rise as glacial melt drives landslides

Geoscientists studying 200m-high wave that hit Greenland coast last year warn of potentially disastrous impact

Just under a year ago, the east coast of Greenland was hit by a megatsunami. Triggered by a large landslide entering the uninhabited Dickson Fjord, the resulting tsunami was 200 metres high – equivalent to more than 40 double-decker buses.

Luckily no one was hurt, though a military base was obliterated. Now analysis of the seismic data associated with the event has revealed that the tsunami was followed by a standing wave, which continued to slosh back and forth within the narrow fjord for many days.

Physicians work to help prevent vision loss associated with space travel

Physicians at the Medical College of Georgia at Augusta University are working with Polaris Dawn, the first of the Polaris Program's three human spaceflight missions, to better understand the eye changes many astronauts experience during spaceflight that can leave them with a wide range of symptoms once they return to Earth—from a new need for glasses to significant loss of vision.

Snowflake shares sink 13% on decelerating product revenue growth

Shares of Snowflake fell after it released fiscal second-quarter 2025 earnings that showed decelerating product revenue growth compared to past quarters.

Evaluating L-band InSAR snow water equivalent retrievals with repeat ground-penetrating radar and terrestrial lidar surveys in northern Colorado

Evaluating L-band InSAR snow water equivalent retrievals with repeat ground-penetrating radar and terrestrial lidar surveys in northern Colorado Randall Bonnell, Daniel McGrath, Jack Tarricone, Hans-Peter Marshall, Ella Bump, Caroline Duncan, Stephanie Kampf, Yunling Lou, Alex Olsen-Mikitowicz, Megan Sears, Keith Williams, Lucas Zeller, and Yang Zheng The Cryosphere, 18, 3765–3785, https://doi.org/10.5194/tc-18-3765-2024, 2024 Snow provides water for billions of people, but the amount of snow is difficult to detect remotely. During the 2020 and 2021 winters, a radar was flown over mountains in Colorado, USA, to measure the amount of snow on the ground, while our team collected ground observations to test the radar technique’s capabilities. The technique yielded accurate measurements of the snowpack that had good correlation with ground measurements, making it a promising application for the upcoming NISAR satellite.

On the relationship between δO2∕N2 variability and ice sheet surface conditions in Antarctica

On the relationship between δO2∕N2 variability and ice sheet surface conditions in Antarctica Romilly Harris Stuart, Amaëlle Landais, Laurent Arnaud, Christo Buizert, Emilie Capron, Marie Dumont, Quentin Libois, Robert Mulvaney, Anaïs Orsi, Ghislain Picard, Frédéric Prié, Jeffrey Severinghaus, Barbara Stenni, and Patricia Martinerie The Cryosphere, 18, 3741–3763, https://doi.org/10.5194/tc-18-3741-2024, 2024 Ice core  δO2/N2 records are useful dating tools due to their local insolation pacing. A precise understanding of the physical mechanism driving this relationship, however, remain ambiguous. By compiling data from 15 polar sites, we find a strong dependence of mean δO2/N2 on accumulation rate and temperature in addition to the well-documented insolation dependence. Snowpack modelling is used to investigate which physical properties drive the mechanistic dependence on these local parameters.

Antarctica vulnerable to invasive species hitching rides on plastic and organic debris

A new study reveals how ocean biology and marine pollution can end up on Antarctica's shoreline.

Rubbish and disease could disrupt Antarctic ecosystems as ice buffers melt, study finds

Simulated study shows southern ecosystems could be compromised by objects from South Africa, South America, New Zealand and Australia as global heating continues

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Antarctic ecosystems could be disrupted by animals, diseases and rubbish floating from Africa and Australia as rising temperatures melt sea ice buffers, new research suggests.

The study, published in the journal Global Change Biology, used a simulation of ocean currents to track the paths of virtual objects released from different locations.

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Snowflake says data breach has not affected core business

Snowflake CEO Sridhar Ramaswamy told CNBC's Jim Cramer about the data breach his company faced earlier this year.

Highest prediction of sea-level rise unlikely

A new study challenges as highly unlikely an alarming prediction of sea-level rise that -- while designated as low likelihood --earned a spot in the latest UN climate report for its projection that the collapse of polar ice sheets could make the world's oceans up to 50 feet higher by 2300. But researchers found that the model is based on inaccurate physics of how ice sheets retreat and break apart, though they stress that the accelerating loss of ice from Greenland and Antarctica is still dire.

New Study Re-Evaluates ‘Worst Case’ Scenario for Thwaites Glacier

Global warming is putting the continent’s ice at risk of destruction in many forms. But one especially calamitous scenario might be a less pressing concern, a new study found.

EarthCARE profiles atmospheric particles in detail

Launched in May, ESA’s EarthCARE satellite has been making waves, with the first images from three of its scientific instruments already delivered. Now, the spotlight is firmly on the atmospheric lidar, the most advanced of the satellite’s four instruments.

This cutting-edge sensor has captured detailed 20 km-high vertical profiles of atmospheric aerosols – tiny particles and droplets from natural sources like wildfires, dust, and sea spray, and from human activities like industrial emissions or burning of wood – and clouds across various regions of the globe.

Under a Frozen Army Base, He Found Incredible Fossils

In a new book, geologist Paul Bierman recounts the moment he found astonishing evidence that Greenland’s ice sheet had melted in the ancient past.

Human-induced borealization leads to the collapse of Bering Sea snow crab

Nature Climate Change, Published online: 21 August 2024; doi:10.1038/s41558-024-02093-0

Daily briefing: ‘Flash droughts’ fuelled devastating Canadian wildfires

Nature, Published online: 21 August 2024; doi:10.1038/d41586-024-02771-1

Everest's Sherpas fear their homes could wash away

Climate change is melting glaciers at unprecedented rates - and putting thousands in Nepal at risk.

New view of North Star reveals spotted surface

Researchers using Georgia State University's Center for High Angular Resolution Astronomy (CHARA) Array have identified new details about the size and appearance of the North Star, also known as Polaris. The new research is published in The Astrophysical Journal.

Astronomers explore the properties of quasar 1604+159

Chinese astronomers have conducted multi-frequency polarimetric observations of a quasar known as 1604+159. Results of the observational campaign, published August 13 on the pre-print server arXiv, shed more light on the properties of this quasar, including its morphology and magnetic field.

Misidentified subglacial lake beneath the Devon Ice Cap, Canadian Arctic: a new interpretation from seismic and electromagnetic data

Misidentified subglacial lake beneath the Devon Ice Cap, Canadian Arctic: a new interpretation from seismic and electromagnetic data Siobhan F. Killingbeck, Anja Rutishauser, Martyn J. Unsworth, Ashley Dubnick, Alison S. Criscitiello, James Killingbeck, Christine F. Dow, Tim Hill, Adam D. Booth, Brittany Main, and Eric Brossier The Cryosphere, 18, 3699–3722, https://doi.org/10.5194/tc-18-3699-2024, 2024 A subglacial lake was proposed to exist beneath Devon Ice Cap in the Canadian Arctic based on the analysis of airborne data. Our study presents a new interpretation of the subglacial material beneath the Devon Ice Cap from surface-based geophysical data. We show that there is no evidence of subglacial water, and the subglacial lake has likely been misidentified. Re-evaluation of the airborne data shows that overestimation of a critical processing parameter has likely occurred in prior studies.

Novel approach to estimate the water isotope diffusion length in deep ice cores with an application to Marine Isotope Stage 19 in the Dome C ice core

Novel approach to estimate the water isotope diffusion length in deep ice cores with an application to Marine Isotope Stage 19 in the Dome C ice core Fyntan Shaw, Andrew M. Dolman, Torben Kunz, Vasileios Gkinis, and Thomas Laepple The Cryosphere, 18, 3685–3698, https://doi.org/10.5194/tc-18-3685-2024, 2024 Fast variability of water isotopes in ice cores is attenuated by diffusion but can be restored if the diffusion length is accurately estimated. Current estimation methods are inadequate for deep ice, mischaracterising millennial-scale climate variability. We address this using variability estimates from shallower ice. The estimated diffusion length of 31 cm for the bottom of the Dome C ice core is 20 cm less than the old method, enabling signal recovery on timescales previously considered lost.

Toward long-term monitoring of regional permafrost thaw with satellite interferometric synthetic aperture radar

Toward long-term monitoring of regional permafrost thaw with satellite interferometric synthetic aperture radar Taha Sadeghi Chorsi, Franz J. Meyer, and Timothy H. Dixon The Cryosphere, 18, 3723–3740, https://doi.org/10.5194/tc-18-3723-2024, 2024 The active layer thaws and freezes seasonally. The annual freeze–thaw cycle of the active layer causes significant surface height changes due to the volume difference between ice and liquid water. We estimate the subsidence rate and active-layer thickness (ALT) for part of northern Alaska for summer 2017 to 2022 using interferometric synthetic aperture radar and lidar. ALT estimates range from ~20 cm to larger than 150 cm in area. Subsidence rate varies between close points (2–18 mm per month).

Civilian Polaris Dawn spacewalk mission is set to launch next week

The planned spacewalk -- a first for a private mission -- will rely on simply opening the spacecraft’s door.

Why record wildfires scorched Canada last year

Nature, Published online: 20 August 2024; doi:10.1038/d41586-024-02653-6

Post-depositional modification on seasonal-to-interannual timescales alters the deuterium-excess signals in summer snow layers in Greenland

Post-depositional modification on seasonal-to-interannual timescales alters the deuterium-excess signals in summer snow layers in Greenland Michael S. Town, Hans Christian Steen-Larsen, Sonja Wahl, Anne-Katrine Faber, Melanie Behrens, Tyler R. Jones, and Arny Sveinbjornsdottir The Cryosphere, 18, 3653–3683, https://doi.org/10.5194/tc-18-3653-2024, 2024 A polar snow isotope dataset from northeast Greenland shows that snow changes isotopically after deposition. Summer snow sometimes enriches in oxygen-18, making it seem warmer than it actually was when the snow fell. Deuterium excess sometimes changes after deposition, making the snow seem to come from warmer, closer, or more humid places. After a year of aging, deuterium excess of summer snow layers always increases. Reinterpretation of deuterium excess used in climate models is necessary.

The waning of Arctic summer

Arctic sea ice continued the fast retreat that was observed in July through August 10, followed by a brief slowdown, only to pick up pace again. During the first half of August, the ice primarily retreated in the northern Beaufort … Continue reading →

The waning of Arctic summer

Arctic sea ice continued the fast retreat that was observed in July through August 10, followed by a brief slowdown, only to pick up pace again. During the first half of August, the ice primarily retreated in the northern Beaufort Sea and in the East Siberian Sea.

The first SpaceX spacewalk: What the Polaris Dawn commander says about the bold upcoming mission

The Polaris Dawn mission is the first of three flights Jared Isaacman bought from SpaceX in 2022 for his human spaceflight effort known as the Polaris Program.

New satellite demonstrates the power of AI for Earth observation

Φsat-2, ESA’s groundbreaking cubesat designed to revolutionise Earth observation with artificial intelligence, has launched.

The cubesat embarked on its journey into space on 16 August at 20:56 CEST (11:56 local time) on board a SpaceX Falcon 9 rocket from the Vandenberg Space Force Base in California, US, integrated by Exolaunch as part of the Transporter-11 rideshare mission, which also included ESA’s Arctic Weather Satellite.

Arctic Weather Satellite lifts off to set the stage for better forecasts

ESA’s Arctic Weather Satellite has been launched, paving the way for a potential constellation of satellites that would provide more frequent data not only to enhance short-term weather forecasts for Arctic nations, but for the world as a whole.

Why isn't Colorado's snowpack ending up in the Colorado River? New research suggests the problem might be the lack of spring rainfall

The Colorado River and its tributaries provide water for hydropower, irrigation and drinking water in seven U.S. states and Mexico. But since 2000, water managers have struggled to predict how much water will come from the snowpack. The problem lies with the lack of rainfall in the spring, according to new research.

Wind tunnel experiments to quantify the effect of aeolian snow transport on the surface snow microstructure

Wind tunnel experiments to quantify the effect of aeolian snow transport on the surface snow microstructure Benjamin Walter, Hagen Weigel, Sonja Wahl, and Henning Löwe The Cryosphere, 18, 3633–3652, https://doi.org/10.5194/tc-18-3633-2024, 2024 The topmost layer of a snowpack forms the interface to the atmosphere and is critical for the reflectance of solar radiation and avalanche formation. The effect of wind on the surface snow microstructure during precipitation events is poorly understood and quantified. We performed controlled lab experiments in a ring wind tunnel to systematically quantify the snow microstructure for different wind speeds, temperatures and precipitation intensities and to identify the relevant processes.

News at a glance: Europe’s heat-related deaths, Antarctic vegetation, and Stonehenge’s faraway stone

The latest in science and policy

As human activities expand in Antarctica, scientists identify crucial conservation sites

Establishing Key Biodiversity Areas in the Southern Ocean will be vital for safeguarding the ecosystem from the impact of human activities, researchers say.

Arctic glacier snowline altitudes rise 150 m over the last 4 decades

Arctic glacier snowline altitudes rise 150 m over the last 4 decades Laura J. Larocca, James M. Lea, Michael P. Erb, Nicholas P. McKay, Megan Phillips, Kara A. Lamantia, and Darrell S. Kaufman The Cryosphere, 18, 3591–3611, https://doi.org/10.5194/tc-18-3591-2024, 2024 Here we present summer snowline altitude (SLA) time series for 269 Arctic glaciers. Between 1984 and 2022, SLAs rose ∼ 150 m, equating to a ∼ 127 m shift per 1 °C of summer warming. SLA is most strongly correlated with annual temperature variables, highlighting their dual effect on ablation and accumulation processes. We show that SLAs are rising fastest on low-elevation glaciers and that > 50 % of the studied glaciers could have SLAs that exceed the maximum ice elevation by 2100.

A physics-based Antarctic melt detection technique: combining Advanced Microwave Scanning Radiometer 2, radiative-transfer modeling, and firn modeling

A physics-based Antarctic melt detection technique: combining Advanced Microwave Scanning Radiometer 2, radiative-transfer modeling, and firn modeling Marissa E. Dattler, Brooke Medley, and C. Max Stevens The Cryosphere, 18, 3613–3631, https://doi.org/10.5194/tc-18-3613-2024, 2024 We developed an algorithm based on combining models and satellite observations to identify the presence of surface melt on the Antarctic Ice Sheet. We find that this method works similarly to previous methods by assessing 13 sites and the Larsen C ice shelf. Unlike previous methods, this algorithm is based on physical parameters, and updates to this method could allow the meltwater present on the Antarctic Ice Sheet to be quantified instead of simply detected.

Improved records of glacier flow instabilities using customized NASA autoRIFT (CautoRIFT) applied to PlanetScope imagery

Improved records of glacier flow instabilities using customized NASA autoRIFT (CautoRIFT) applied to PlanetScope imagery Jukes Liu, Madeline Gendreau, Ellyn Mary Enderlin, and Rainey Aberle The Cryosphere, 18, 3571–3590, https://doi.org/10.5194/tc-18-3571-2024, 2024 There are sometimes gaps in global glacier velocity records produced using satellite image feature-tracking algorithms during times of rapid glacier acceleration, which hinders the study of glacier flow processes. We present an open-source pipeline for customizing the feature-tracking parameters and for including images from an additional source. We applied it to five glaciers and found that it produced accurate velocity data that supplemented their velocity records during rapid acceleration.

A belly full of jelly

For a long time, scientists assumed that jellies (commonly known as jellyfish) were a dead-end food source for predatory fish. However, a team has now discovered that fish in Greenland waters do indeed feed on jellyfish. In two of the analyzed species, they even made up the majority of the food. The results suggest that the role of jellyfish as prey in marine food webs should be reconsidered, especially in regards to the fact that they could be profiting from climate change and spreading farther and farther north.

Unimolecular net heterolysis of symmetric and homopolar σ-bonds

Nature, Published online: 14 August 2024; doi:10.1038/s41586-024-07622-7

Two polar bears kill Canadian worker in rare attack

The person who was killed worked at a remote radar site in Canada's Arctic region.

Crypto magnate buys SpaceX mission for private polar spaceflight expedition

Cryptocurrency speculator Chun Wang bought a SpaceX multi-day flight for an undisclosed amount, the company announced on Monday.

SpaceX announces new private mission on 1st human polar orbit spaceflight

SpaceX has lined up more business for its human spaceflight program with a private launch from Florida that will take its passengers on a polar orbit for the first time.

Arctic Weather Satellite: advancing weather forecasting in a changing climate

Video: 00:04:38

The effects of the climate crisis are felt more acutely in the Arctic than anywhere else on the planet. The weather in the Arctic is not only severe, but it changes extremely quickly. More frequent data are urgently needed to improve weather forecasts for this susceptible polar region.

Enter ESA’s Arctic Weather Satellite: a brand new prototype mission to show exactly how this can be achieved. The satellite will provide precise, short-term weather forecasts for the Arctic region. It is equipped with a 19-channel cross-track scanning microwave radiometer which will provide high-resolution humidity and temperature soundings of the atmosphere in all weather conditions.

The Arctic Weather Satellite is the forerunner of a potential constellation of satellites, called EPS-Sterna, that ESA would build for Eumetsat if this first prototype Arctic Weather Satellite performs well.

New hope of finding life on Mars after indication of water, scientists say

Liquid amounting to a 1-2km-deep ocean may be frozen up to 20km below surface, calculations suggest

Vast amounts of water could be trapped deep within the crust of Mars, scientists have said, raising fresh questions about the possibility of life on the red planet.

Scientists say that more than 3bn years ago, Mars not only had lakes and rivers but oceans on its surface – however, as the planet lost its atmosphere these bodies disappeared. All that is visible today is permafrost ice at the planet’s poles.

Dynamic and thermodynamic processes related to sea-ice surface melt advance in the Laptev Sea and East Siberian Sea

Dynamic and thermodynamic processes related to sea-ice surface melt advance in the Laptev Sea and East Siberian Sea Hongjie Liang and Wen Zhou The Cryosphere, 18, 3559–3569, https://doi.org/10.5194/tc-18-3559-2024, 2024 This study identifies the metric of springtime sea-ice surface melt advance in the Laptev Sea and East Siberian Sea, which can be defined on the same date each year and has the potential to be used in the practical seasonal prediction of summer sea ice cover instead of average melt onset. Detailed analysis of dynamic and thermodynamic processes related to different melt advance scenarios in this region imply considerable interannual and interdecadal variability in springtime conditions.

Long-distance relationship revealed in the seemingly random behavior of bowhead whales

Applying chaos theory to the movement of iconic arctic whales uncovered a 24-hour diving cycle and a long-range (~100 km) synchronization.

Reduced Arctic Ocean CO₂ uptake due to coastal permafrost erosion

Nature Climate Change, Published online: 12 August 2024; doi:10.1038/s41558-024-02074-3

Climate feedbacks from coastal erosion

Nature Climate Change, Published online: 12 August 2024; doi:10.1038/s41558-024-02089-w

Ancient Poppy Seeds And Willow Wood Offer Clues To Ice Sheet’s Last Meltdown

A tiny elongate poppy seed and small tan spikemoss megaspores and black soil fungus spheres were found in soil recovered from under 2 miles of Greenland’s ice.

Snow redistribution in an intermediate-complexity snow hydrology modelling framework

Snow redistribution in an intermediate-complexity snow hydrology modelling framework Louis Quéno, Rebecca Mott, Paul Morin, Bertrand Cluzet, Giulia Mazzotti, and Tobias Jonas The Cryosphere, 18, 3533–3557, https://doi.org/10.5194/tc-18-3533-2024, 2024 Snow redistribution by wind and avalanches strongly influences snow hydrology in mountains. This study presents a novel modelling approach to best represent these processes in an operational context. The evaluation of the simulations against airborne snow depth measurements showed remarkable improvement in the snow distribution in mountains of the eastern Swiss Alps, with a representation of snow accumulation and erosion areas, suggesting promising benefits for operational snow melt forecasts.

Spatial variation in the specific surface area of surface snow measured along the traverse route from the coast to Dome Fuji, Antarctica, during austral summer

Spatial variation in the specific surface area of surface snow measured along the traverse route from the coast to Dome Fuji, Antarctica, during austral summer Ryo Inoue, Teruo Aoki, Shuji Fujita, Shun Tsutaki, Hideaki Motoyama, Fumio Nakazawa, and Kenji Kawamura The Cryosphere, 18, 3513–3531, https://doi.org/10.5194/tc-18-3513-2024, 2024 We measured the snow specific surface area (SSA) at ~2150 surfaces between the coast near Syowa Station and Dome Fuji, East Antarctica, in summer 2021–2022. The observed SSA shows no elevation dependence between 15 and 500 km from the coast and increases toward the dome area beyond the range. SSA varies depending on surface morphologies and meteorological events. The spatial variation of SSA can be explained by snow metamorphism, snowfall frequency, and wind-driven inhibition of snow deposition.

Greenland mega-tsunami led to week-long oscillating fjord wave

In September 2023, a megatsunami in remote eastern Greenland sent seismic waves around the world, piquing the interest of the global research community. The event created a week-long oscillating wave in Dickson Fjord, according to a new report in The Seismic Record.

Reanalyzing the spatial representativeness of snow depth at automated monitoring stations using airborne lidar data

Reanalyzing the spatial representativeness of snow depth at automated monitoring stations using airborne lidar data Jordan N. Herbert, Mark S. Raleigh, and Eric E. Small The Cryosphere, 18, 3495–3512, https://doi.org/10.5194/tc-18-3495-2024, 2024 Automated stations measure snow properties at a single point but are frequently used to validate data that represent much larger areas. We use lidar snow depth data to see how often the mean snow depth surrounding a snow station is within 10 cm of the snow station depth at different scales. We found snow stations overrepresent the area-mean snow depth in ~ 50 % of cases, but the direction of bias at a site is temporally consistent, suggesting a site could be calibrated to the surrounding area.

The AutoICE Challenge

The AutoICE Challenge Andreas Stokholm, Jørgen Buus-Hinkler, Tore Wulf, Anton Korosov, Roberto Saldo, Leif Toudal Pedersen, David Arthurs, Ionut Dragan, Iacopo Modica, Juan Pedro, Annekatrien Debien, Xinwei Chen, Muhammed Patel, Fernando Jose Pena Cantu, Javier Noa Turnes, Jinman Park, Linlin Xu, Katharine Andrea Scott, David Anthony Clausi, Yuan Fang, Mingzhe Jiang, Saeid Taleghanidoozdoozan, Neil Curtis Brubacher, Armina Soleymani, Zacharie Gousseau, Michał Smaczny, Patryk Kowalski, Jacek Komorowski, David Rijlaarsdam, Jan Nicolaas van Rijn, Jens Jakobsen, Martin Samuel James Rogers, Nick Hughes, Tom Zagon, Rune Solberg, Nicolas Longépé, and Matilde Brandt Kreiner The Cryosphere, 18, 3471–3494, https://doi.org/10.5194/tc-18-3471-2024, 2024 The AutoICE challenge encouraged the development of deep learning models to map multiple aspects of sea ice – the amount of sea ice in an area and the age and ice floe size – using multiple sources of satellite and weather data across the Canadian and Greenlandic Arctic. Professionally drawn operational sea ice charts were used as a reference. A total of 179 students and sea ice and AI specialists participated and produced maps in broad agreement with the sea ice charts.

Increasing numerical stability of mountain valley glacier simulations: implementation and testing of free-surface stabilization in Elmer/Ice

Increasing numerical stability of mountain valley glacier simulations: implementation and testing of free-surface stabilization in Elmer/Ice André Löfgren, Thomas Zwinger, Peter Råback, Christian Helanow, and Josefin Ahlkrona The Cryosphere, 18, 3453–3470, https://doi.org/10.5194/tc-18-3453-2024, 2024 This paper investigates a stabilization method for free-surface flows in the context of glacier simulations. Previous applications of the stabilization on ice flows have only considered simple ice-sheet benchmark problems; in particular the method had not been tested on real-world glacier domains. This work addresses this shortcoming by demonstrating that the stabilization works well also in this case and increases stability and robustness without negatively impacting computation times.

The chill is gone

Arctic sea ice cover retreated rapidly in July 2024, pushing the daily ice extent at the end of the month to the third lowest in the 46-year satellite record. Extensive low-concentration areas of sea ice are found in the Beaufort and East Siberian Seas, reaching 85 degrees North. In the Southern Ocean, sea ice is nearing the extreme low record extent set just last year, caused mostly by a large ice-free area in the southwestern Indian Ocean. As a result, global sea ice extent is at record lows for this time of year.

How does space change the human body? The answer will shapes future missions

Space X’s highly anticipated Polaris Dawn mission is set to launch later this summer – with an all-civilian crew. And a big part of their mission is researching how space changes the human body.

Antarctic-wide survey of plant life to aid conservation efforts

The first continent-wide mapping study of plant life across Antarctica reveals growth in previously uncharted areas and is set to inform conservation measures across the region. The satellite survey of mosses, lichens and algae across the continent will form a baseline for monitoring how Antarctica's vegetation responds to climate change.

The potential of in situ cosmogenic 14CO in ice cores as a proxy for galactic cosmic ray flux variations

The potential of in situ cosmogenic 14CO in ice cores as a proxy for galactic cosmic ray flux variations Vasilii V. Petrenko, Segev BenZvi, Michael Dyonisius, Benjamin Hmiel, Andrew M. Smith, and Christo Buizert The Cryosphere, 18, 3439–3451, https://doi.org/10.5194/tc-18-3439-2024, 2024 This manuscript presents the concept for a new proxy for past variations in the galactic cosmic ray flux (GCR). Past variations in GCR flux are important to understand for interpretation of records of isotopes produced by cosmic rays; these records are used for reconstructing solar variations and past land ice extent. The proxy involves using measurements of 14CO in ice cores, which should provide an uncomplicated and precise estimate of past GCR flux variations for the past few thousand years.

The chill is gone

Arctic sea ice cover retreated rapidly in July 2024, pushing the daily ice extent at the end of the month to the third lowest in the 46-year satellite record. Extensive low-concentration areas of sea ice are found in the Beaufort and East Siberian Seas, … Continue reading →

A satellite-derived baseline of photosynthetic life across Antarctica

Nature Geoscience, Published online: 06 August 2024; doi:10.1038/s41561-024-01492-4

Unmasking Antarctica’s biodiversity

Nature Geoscience, Published online: 06 August 2024; doi:10.1038/s41561-024-01502-5

Greenland fossil discovery reveals increased risk of sea-level catastrophe

Seeds, twigs, and insect parts found under two miles of ice confirm Greenland's ice sheet melted in the recent past, the first direct evidence that the center -- not just the edges -- of the two-mile-deep ice melted away in the recent geological past. The new research indicates that the giant ice sheet is more fragile than scientists had realized until the last few years -- and reveals increased risk of sea-level catastrophe in a warmer future.

How the rising earth in Antarctica will impact future sea level rise

The rising earth beneath the Antarctic Ice Sheet will likely become a major factor in future sea level rise, a new study suggests.

Link between global warming and rising sea levels

A new study suggests that Earth's natural forces could substantially reduce Antarctica's impact on rising sea levels, but only if carbon emissions are swiftly reduced in the coming decades. By the same token, if emissions continue on the current trajectory, Antarctic ice loss could lead to more future sea level rise than previously thought.

Retreat of tropical glaciers foreshadows changing climate's effect on the global ice

As they are in many places around the globe, glaciers perched high in the Andes Mountains are shrinking. Now, researchers have uncovered evidence that the high-altitude tropical ice fields are likely smaller than they've been at any time since the last ice age ended 11,700 years ago.

Climate change may lead to shifts in vital Pacific Arctic fisheries

Commercially important marine fish and invertebrate species will likely shift northwards under a warmer climate, according to new research.

Tipping risks from overshooting 1.5 °C can be minimized if warming is swiftly reversed

Current climate policies imply a high risk for tipping of critical Earth system elements, even if temperatures return to below 1.5 C of global warming after a period of overshoot. A new study indicates that this risk can be minimized if the warming is swiftly reversed. That is why reducing emissions in the current decade is crucial for the stability of the Earth systems functions, researchers write. They analyzed the tipping risks for four interconnected core climate tipping elements: the Greenland Ice Sheet, the West Antarctic Ice Sheet, the Atlantic Meridional Overturning Circulation (AMOC), and the Amazon Rainforest.

Arctic ice thinner near Canada; thicker elsewhere

The Arctic sea ice cover in June 2024 retreated at a below average pace, leading to a larger total sea ice extent for the month than in recent years. Many areas of open water have developed along the Arctic Ocean coast. Sea ice in Hudson Bay continues to track at the lowest levels seen in the satellite data record. In the Antarctic, extent remains above the 2023 record-setting low extent but is still well below all other years in the satellite era.

Underwater mapping reveals new insights into melting of Antarctica's ice shelves

Clues to future sea level rise have been revealed by the first detailed maps of the underside of a floating ice shelf in Antarctica. An international research team deployed an unmanned submersible beneath the Dotson Ice Shelf in West Antarctica.

Robot Captures Pictures of the Dotson Ice Shelf in Antarctica

The new images of the melting underside of an ice shelf could help scientists better forecast how the continent is contributing to rising sea levels.

Astronomers find anomalies in star V889 Herculis's rotation

The sun rotates the fastest at the equator, whereas the rotation rate slows down at higher latitudes and is the slowest at the polar regions. But a nearby sun-like star—V889 Herculis, some 115 light years away in the constellation of Hercules—rotates the fastest at a latitude of about 40 degrees, while both the equator and polar regions rotate more slowly. This finding has been published in Astronomy & Astrophysics.

The development of terrestrial ecosystems emerging after glacier retreat

Nature, Published online: 31 July 2024; doi:10.1038/s41586-024-07778-2

First map of an ice shelf’s bottom reveals mysterious melt patterns

Nature, Published online: 31 July 2024; doi:10.1038/d41586-024-02501-7

Brief communication: Precision measurement of the index of refraction of deep glacial ice at radio frequencies at Summit Station, Greenland

Brief communication: Precision measurement of the index of refraction of deep glacial ice at radio frequencies at Summit Station, Greenland Christoph Welling and The RNO-G Collaboration The Cryosphere, 18, 3433–3437, https://doi.org/10.5194/tc-18-3433-2024, 2024 We report on the measurement of the index of refraction in glacial ice at radio frequencies. We show that radio echoes from within the ice can be associated with specific features of the ice conductivity and use this to determine the wave velocity. This measurement is especially relevant for the Radio Neutrino Observatory Greenland (RNO-G), a neutrino detection experiment currently under construction at Summit Station, Greenland.

Polar bear threat for Arctic researchers

Nature, Published online: 30 July 2024; doi:10.1038/d41586-024-02496-1

Local food production saves costs and carbon

Emphasizing local food production over imported substitutes can lead to significant cost and carbon savings, according to data from the Inuvialuit Settlement Region in the Canadian Arctic. The research shows potential annual savings of more than 3.1 million Canadian dollars and roughly half the carbon emissions when locally harvested food is used instead of imported food. The study underscores the importance of climate change policies that take local food systems into account. Weakening of these local systems could lead to increased emissions and jeopardize the health and food security of remote communities.

Sea-ice conditions from 1880 to 2017 on the Northeast Greenland continental shelf: a biomarker and observational record comparison

Sea-ice conditions from 1880 to 2017 on the Northeast Greenland continental shelf: a biomarker and observational record comparison Joanna Davies, Kirsten Fahl, Matthias Moros, Alice Carter-Champion, Henrieka Detlef, Ruediger Stein, Christof Pearce, and Marit-Solveig Seidenkrantz The Cryosphere, 18, 3415–3431, https://doi.org/10.5194/tc-18-3415-2024, 2024 Here, we evaluate the use of biomarkers for reconstructing sea ice between 1880 and 2017 from three sediment cores located in a transect across the Northeast Greenland continental shelf. We find that key changes, specifically the decline in sea-ice cover identified in observational records between 1971 and 1984, align with our biomarker reconstructions. This outcome supports the use of biomarkers for longer reconstructions of sea-ice cover in this region.

Decadal increases in carbon uptake offset by respiratory losses across northern permafrost ecosystems

Nature Climate Change, Published online: 26 July 2024; doi:10.1038/s41558-024-02057-4

Warming has more impact than cooling on Greenland's 'firn'

A new study finds disproportionate effects of temperature shifts on an icy glacier layer.

Expert Q&A: NASA's cancellation of VIPER is a frustrating setback for lunar exploration

In July 2024, NASA announced it canceled its plans to send the Volatiles Investigating Polar Exploration Rover (VIPER) to the moon's southern polar region. The rover was meant to search for water and other resources called volatiles, such as hydrogen, ammonia and carbon dioxide, which easily evaporate in warm temperatures.

Spectral induced polarization imaging to monitor seasonal and annual dynamics of frozen ground at a mountain permafrost site in the Italian Alps

Spectral induced polarization imaging to monitor seasonal and annual dynamics of frozen ground at a mountain permafrost site in the Italian Alps Theresa Maierhofer, Adrian Flores Orozco, Nathalie Roser, Jonas K. Limbrock, Christin Hilbich, Clemens Moser, Andreas Kemna, Elisabetta Drigo, Umberto Morra di Cella, and Christian Hauck The Cryosphere, 18, 3383–3414, https://doi.org/10.5194/tc-18-3383-2024, 2024 In this study, we apply an electrical method in a high-mountain permafrost terrain in the Italian Alps, where long-term borehole temperature data are available for validation. In particular, we investigate the frequency dependence of the electrical properties for seasonal and annual variations along a 3-year monitoring period. We demonstrate that our method is capable of resolving temporal changes in the thermal state and the ice / water ratio associated with seasonal freeze–thaw processes.

Characterization of in situ cosmogenic 14CO production, retention and loss in firn and shallow ice at Summit, Greenland

Characterization of in situ cosmogenic 14CO production, retention and loss in firn and shallow ice at Summit, Greenland Benjamin Hmiel, Vasilii V. Petrenko, Christo Buizert, Andrew M. Smith, Michael N. Dyonisius, Philip Place, Bin Yang, Quan Hua, Ross Beaudette, Jeffrey P. Severinghaus, Christina Harth, Ray F. Weiss, Lindsey Davidge, Melisa Diaz, Matthew Pacicco, James A. Menking, Michael Kalk, Xavier Faïn, Alden Adolph, Isaac Vimont, and Lee T. Murray The Cryosphere, 18, 3363–3382, https://doi.org/10.5194/tc-18-3363-2024, 2024 The main aim of this research is to improve understanding of carbon-14 that is produced by cosmic rays in ice sheets. Measurements of carbon-14 in ice cores can provide a range of useful information (age of ice, past atmospheric chemistry, past cosmic ray intensity). Our results show that almost all (>99 %) of carbon-14 that is produced in the upper layer of ice sheets is rapidly lost to the atmosphere. Our results also provide better estimates of carbon-14 production rates in deeper ice.

Southern Ocean absorbing more carbon dioxide than previously thought, study finds

New research has found that the Southern Ocean absorbs more carbon dioxide (CO2) than previously thought. Using direct measurements of CO2 exchange, or fluxes, between the air and sea, the scientists found the ocean around Antarctica absorbs 25% more CO2 than previous indirect estimates based on shipboard data have suggested.

Greenland's firn responds more to warming than to cooling

Greenland's firn responds more to warming than to cooling Megan Thompson-Munson, Jennifer E. Kay, and Bradley R. Markle The Cryosphere, 18, 3333–3350, https://doi.org/10.5194/tc-18-3333-2024, 2024 The upper layers of the Greenland Ice Sheet are absorbent and can store meltwater that would otherwise flow into the ocean and raise sea level. The amount of meltwater that the ice sheet can store changes when the air temperature changes. We use a model to show that warming and cooling have opposite but unequal effects. Warming has a stronger effect than cooling, which highlights the vulnerability of the Greenland Ice Sheet to modern climate change.

Research into mechanical modeling based on characteristics of the fracture mechanics of ice cutting for scientific drilling in polar regions

Research into mechanical modeling based on characteristics of the fracture mechanics of ice cutting for scientific drilling in polar regions Xinyu Lv, Zhihao Cui, Ting Wang, Yumin Wen, An Liu, and Rusheng Wang The Cryosphere, 18, 3351–3362, https://doi.org/10.5194/tc-18-3351-2024, 2024 In this study, the formation process of ice chips was observed and the fracture mechanics characteristics of the ice during the cutting process were analyzed. Additionally, a mechanical model for the cutting force was established based on the observation and analysis results. Finally, influencing factors and laws of the cutting force were verified by cutting force test results generated under various experimental conditions.

Calving front monitoring at a subseasonal resolution: a deep learning application for Greenland glaciers

Calving front monitoring at a subseasonal resolution: a deep learning application for Greenland glaciers Erik Loebel, Mirko Scheinert, Martin Horwath, Angelika Humbert, Julia Sohn, Konrad Heidler, Charlotte Liebezeit, and Xiao Xiang Zhu The Cryosphere, 18, 3315–3332, https://doi.org/10.5194/tc-18-3315-2024, 2024 Comprehensive datasets of calving-front changes are essential for studying and modeling outlet glaciers. Current records are limited in temporal resolution due to manual delineation. We use deep learning to automatically delineate calving fronts for 23 glaciers in Greenland. Resulting time series resolve long-term, seasonal, and subseasonal patterns. We discuss the implications of our results and provide the cryosphere community with a data product and an implementation of our processing system.

Scientists call for greater study of glacier geoengineering options

Report says serious research needed into risks and benefits as melting could cause devastating sea level rise

We need to seriously consider geoengineering projects to save our glaciers or face catastrophic sea level rise, scientists say in a report.

Antarctica and Greenland’s ice sheets are melting fast and even if we manage to reduce carbon emissions and limit global heating to 2C, it is not clear if that will be enough to prevent ice sheet collapse. But geoengineering glaciers may be a way to buy us vital time, the authors of the report argue.

Measuring prairie snow water equivalent with combined UAV-borne gamma spectrometry and lidar

Measuring prairie snow water equivalent with combined UAV-borne gamma spectrometry and lidar Phillip Harder, Warren D. Helgason, and John W. Pomeroy The Cryosphere, 18, 3277–3295, https://doi.org/10.5194/tc-18-3277-2024, 2024 Remote sensing the amount of water in snow (SWE) at high spatial resolutions is an unresolved challenge. In this work, we tested a drone-mounted passive gamma spectrometer to quantify SWE. We found that the gamma observations could resolve the average and spatial variability of SWE down to 22.5 m resolutions. Further, by combining drone gamma SWE and lidar snow depth we could estimate SWE at sub-metre resolutions which is a new opportunity to improve the measurement of shallow snowpacks.

The radiative and geometric properties of melting first-year landfast sea ice in the Arctic

The radiative and geometric properties of melting first-year landfast sea ice in the Arctic Nathan J. M. Laxague, Christopher J. Zappa, Andrew R. Mahoney, John Goodwin, Cyrus Harris, Robert E. Schaeffer, Roswell Schaeffer Sr., Sarah Betcher, Donna D. W. Hauser, Carson R. Witte, Jessica M. Lindsay, Ajit Subramaniam, Kate E. Turner, and Alex Whiting The Cryosphere, 18, 3297–3313, https://doi.org/10.5194/tc-18-3297-2024, 2024 The state of sea ice strongly affects its absorption of solar energy. In May 2019, we flew uncrewed aerial vehicles (UAVs) equipped with sensors designed to quantify the sunlight that is reflected by sea ice at each wavelength over the sea ice of Kotzebue Sound, Alaska. We found that snow patches get darker (up to ~ 20 %) as they get smaller, while bare patches get darker (up to ~ 20 %) as they get larger. We believe that this difference is due to melting around the edges of small features.

Scientists are tracking polar bears to keep them -- and people safe

In Canada, melting sea ice is forcing polar bears closer and closer to human populations, so scientists there are working on a program to track polar bears, tag them with GPS units and monitor their movement.

Spatially distributed snow depth, bulk density, and snow water equivalent from ground-based and airborne sensor integration at Grand Mesa, Colorado, USA

Spatially distributed snow depth, bulk density, and snow water equivalent from ground-based and airborne sensor integration at Grand Mesa, Colorado, USA Tate G. Meehan, Ahmad Hojatimalekshah, Hans-Peter Marshall, Elias J. Deeb, Shad O'Neel, Daniel McGrath, Ryan W. Webb, Randall Bonnell, Mark S. Raleigh, Christopher Hiemstra, and Kelly Elder The Cryosphere, 18, 3253–3276, https://doi.org/10.5194/tc-18-3253-2024, 2024 Snow water equivalent (SWE) is a critical parameter for yearly water supply forecasting and can be calculated by multiplying the snow depth by the snow density. We combined high-spatial-resolution snow depth information with ground-based radar measurements to solve for snow density. Extrapolated density estimates over our study area resolved detailed patterns that agree with the known interactions of snow with wind, terrain, and vegetation and were utilized in the calculation of SWE.

Veteran anti-whaling activist arrested in Greenland

Paul Watson could now be extradited to Japan to face charges related to his anti-whaling activism.

Anti-whaling activist arrested in Greenland, could be extradited to Japan

Canadian-American activist Paul Watson was en route to the North Pacific on a mission to intercept a new Japanese whaling ship when police boarded his vessel.

As Wildfires Explode, Smoke Billows Across a Vast Expanse of North America

Dramatic remote sensing imagery reveals the large-scale impact of wildfires, which also are raging in the United States and the Siberian Arctic.

Widespread increase in discharge from west Antarctic Peninsula glaciers since 2018

Widespread increase in discharge from west Antarctic Peninsula glaciers since 2018 Benjamin J. Davison, Anna E. Hogg, Carlos Moffat, Michael P. Meredith, and Benjamin J. Wallis The Cryosphere, 18, 3237–3251, https://doi.org/10.5194/tc-18-3237-2024, 2024 Using a new dataset of ice motion, we observed glacier acceleration on the west coast of the Antarctic Peninsula. The speed-up began around January 2021, but some glaciers sped up earlier or later. Using a combination of ship-based ocean temperature observations and climate models, we show that the speed-up coincided with a period of unusually warm air and ocean temperatures in the region.

Business owner goes viral for mass 'Trump 2024' email—why he missed the mark, from a 'productive discourse' expert

Sticker Mule co-founder Anthony Constantino went viral after sending out a polarizing political memo. Here's what he could have done differently, says an expert.

Although tiny, peatland microorganisms have a big impact on climate

Polyphenols are generally toxic to microorganisms. In peatlands, scientists thought microorganisms avoided this toxicity by degrading polyphenols using an oxygen-dependent enzyme, and thus that low-oxygen conditions inhibit microbes' carbon cycling. However, a new study found that Arctic peatland microorganisms used alternative enzymes, with and without oxygen, to break down polyphenols. This suggests carbon stored in these ecosystems is more at risk than previously thought.

Sea ice's cooling power is waning faster than its area of extent

As sea ice disappears and grows less reflective, the Arctic has lost around a quarter of its cooling power since 1980, and the world has lost up to 15%, according to new research.

New tech aims to keep polar bears and people apart

Fears about the two species coming into contact are growing as Arctic sea ice melts.

Warming oceans are pushing harmful algal blooms into polar waters

Alaska’s Bering Strait was hit by an unprecedented bloom of toxic organisms, which cause paralytic shellfish poisoning, in 2022

Observing glacier elevation changes from spaceborne optical and radar sensors – an inter-comparison experiment using ASTER and TanDEM-X data

Observing glacier elevation changes from spaceborne optical and radar sensors – an inter-comparison experiment using ASTER and TanDEM-X data Livia Piermattei, Michael Zemp, Christian Sommer, Fanny Brun, Matthias H. Braun, Liss M. Andreassen, Joaquín M. C. Belart, Etienne Berthier, Atanu Bhattacharya, Laura Boehm Vock, Tobias Bolch, Amaury Dehecq, Inés Dussaillant, Daniel Falaschi, Caitlyn Florentine, Dana Floricioiu, Christian Ginzler, Gregoire Guillet, Romain Hugonnet, Matthias Huss, Andreas Kääb, Owen King, Christoph Klug, Friedrich Knuth, Lukas Krieger, Jeff La Frenierre, Robert McNabb, Christopher McNeil, Rainer Prinz, Louis Sass, Thorsten Seehaus, David Shean, Désirée Treichler, Anja Wendt, and Ruitang Yang The Cryosphere, 18, 3195–3230, https://doi.org/10.5194/tc-18-3195-2024, 2024 Satellites have made it possible to observe glacier elevation changes from all around the world. In the present study, we compared the results produced from two different types of satellite data between different research groups and against validation measurements from aeroplanes. We found a large spread between individual results but showed that the group ensemble can be used to reliably estimate glacier elevation changes and related errors from satellite data.

Brief communication: On the potential of seismic polarity reversal to identify a thin low-velocity layer above a high-velocity layer in ice-rich rock glaciers

Brief communication: On the potential of seismic polarity reversal to identify a thin low-velocity layer above a high-velocity layer in ice-rich rock glaciers Jacopo Boaga, Mirko Pavoni, Alexander Bast, and Samuel Weber The Cryosphere, 18, 3231–3236, https://doi.org/10.5194/tc-18-3231-2024, 2024 Reversal polarity is observed in rock glacier seismic refraction tomography. We collected several datasets observing this phenomenon in Switzerland and Italy. This phase change may be linked to interferences due to the presence of a thin low-velocity layer. Our results are confirmed by the modelling and analysis of synthetic seismograms to demonstrate that the presence of a low-velocity layer produces a polarity reversal on the seismic gather.

Peak of the melt season

July is the warmest month in the Arctic and hence also the month of peak sea ice loss. As of the middle of July 2024, extent is declining at an above average pace. Sea is mostly gone in Hudson Bay, … Continue reading →

Ground surface conditions impact speed and distance of leaking natural gas

When natural gas leaks from a subsurface pipeline, a ground cover of water/snow saturation, asphalt paving or a combination of these can cause the gas to migrate away from the leak site up to three to four times farther than through dry soil, a new study has found. A research team also found that these surface conditions can impact the speed of the leaked gas, as well, traveling 3.5 times faster than an equivalent leak under dry soil conditions.

Local dragonflies expose mercury pollution patterns

A new study has unveiled surprising findings about mercury pollution: where it comes from and how it moves through the environment vary significantly depending on the ecosystem. In drier regions, most mercury is deposited through rain and snow. In wetter, forested areas, gaseous mercury from the air sticks to leaves, which then fall and carry the toxin into the ground.

Freezer holding world’s biggest ancient-ice archive to get ‘future-proofed’

Nature, Published online: 16 July 2024; doi:10.1038/d41586-024-02287-8

Peak of the melt season

July is the warmest month in the Arctic and hence also the month of peak sea ice loss. As of the middle of July 2024, extent is declining at an above average pace. Sea is mostly gone in Hudson Bay, and there has been extensive retreat in the Barents and Laptev Seas. Satellite data reveal a small area of unusually dense sea ice formed last winter near Wrangel Island.

To avoid sea level rise, some researchers want to build barriers around the world’s most vulnerable glaciers

Call to study glacial geoengineering stirs up “civil war” among polar scientists

Contributions of core, mantle and climatological processes to Earth’s polar motion

Nature Geoscience, Published online: 12 July 2024; doi:10.1038/s41561-024-01478-2

Scientists call for 'major initiative' to study whether geoengineering should be used on glaciers

Scientists have released a landmark report on glacial geoengineering -- an emerging field studying whether technology could halt the melting of glaciers and ice sheets as climate change progresses.

Short-term cooling, drying, and deceleration of an ice-rich rock glacier

Short-term cooling, drying, and deceleration of an ice-rich rock glacier Alexander Bast, Robert Kenner, and Marcia Phillips The Cryosphere, 18, 3141–3158, https://doi.org/10.5194/tc-18-3141-2024, 2024 We monitor ground temperature, water pressure, and relative ice/water contents in a creeping ice-rich rock glacier in mountain permafrost to study its characteristics during a deceleration period with dry conditions and a summer heat wave. The snowpack has an important role as a provider of water and as a thermal insulator. Snow-poor winters, followed by dry summers, induce cooling and drying of the permafrost, leading to rock glacier deceleration.

Two-dimensional numerical simulations of mixing under ice keels

Two-dimensional numerical simulations of mixing under ice keels Sam De Abreu, Rosalie M. Cormier, Mikhail G. Schee, Varvara E. Zemskova, Erica Rosenblum, and Nicolas Grisouard The Cryosphere, 18, 3159–3176, https://doi.org/10.5194/tc-18-3159-2024, 2024 Arctic sea ice is becoming more mobile and thinner, which will affect the upper Arctic Ocean in unforeseen ways. Using numerical simulations, we find that mixing by ice keels (ridges underlying sea ice) depends significantly on their speeds and depths and the density structure of the upper ocean. Large uncertainties in our results highlight the need for more realistic numerical simulations and better measurements of ice keel characteristics.

Tower-based C-band radar measurements of an alpine snowpack

Tower-based C-band radar measurements of an alpine snowpack Isis Brangers, Hans-Peter Marshall, Gabrielle De Lannoy, Devon Dunmire, Christian Mätzler, and Hans Lievens The Cryosphere, 18, 3177–3193, https://doi.org/10.5194/tc-18-3177-2024, 2024 To better understand the interactions between C-band radar waves and snow, a tower-based experiment was set up in the Idaho Rocky Mountains. The reflections were collected in the time domain to measure the backscatter profile from the various snowpack and ground surface layers. The results demonstrate that C-band radar is sensitive to seasonal patterns in snow accumulation but that changes in microstructure, stratigraphy and snow wetness may complicate satellite-based snow depth retrievals.

A study of sea ice topography in the Weddell and Ross seas using dual-polarimetric TanDEM-X imagery

A study of sea ice topography in the Weddell and Ross seas using dual-polarimetric TanDEM-X imagery Lanqing Huang and Irena Hajnsek The Cryosphere, 18, 3117–3140, https://doi.org/10.5194/tc-18-3117-2024, 2024 Interferometric synthetic aperture radar can measure the total freeboard of sea ice but can be biased when radar signals penetrate snow and ice. We develop a new method to retrieve the total freeboard and analyze the regional variation of total freeboard and roughness in the Weddell and Ross seas. We also investigate the statistical behavior of the total freeboard for diverse ice types. The findings enhance the understanding of Antarctic sea ice topography and its dynamics in a changing climate.

Seasonal and diurnal variability of sub-ice platelet layer thickness in McMurdo Sound from electromagnetic induction sounding

Seasonal and diurnal variability of sub-ice platelet layer thickness in McMurdo Sound from electromagnetic induction sounding Gemma M. Brett, Greg H. Leonard, Wolfgang Rack, Christian Haas, Patricia J. Langhorne, Natalie J. Robinson, and Anne Irvin The Cryosphere, 18, 3049–3066, https://doi.org/10.5194/tc-18-3049-2024, 2024 Glacial meltwater with ice crystals flows from beneath ice shelves, causing thicker sea ice with sub-ice platelet layers (SIPLs) beneath. Thicker sea ice and SIPL reveal where and how much meltwater is outflowing. We collected continuous measurements of sea ice and SIPL. In winter, we observed rapid SIPL growth with strong winds. In spring, SIPLs grew when tides caused offshore circulation. Wind-driven and tidal circulation influence glacial meltwater outflow from ice shelf cavities.

Analyzing the sensitivity of a blowing snow model (SnowPappus) to precipitation forcing, blowing snow, and spatial resolution

Analyzing the sensitivity of a blowing snow model (SnowPappus) to precipitation forcing, blowing snow, and spatial resolution Ange Haddjeri, Matthieu Baron, Matthieu Lafaysse, Louis Le Toumelin, César Deschamps-Berger, Vincent Vionnet, Simon Gascoin, Matthieu Vernay, and Marie Dumont The Cryosphere, 18, 3081–3116, https://doi.org/10.5194/tc-18-3081-2024, 2024 Our study addresses the complex challenge of evaluating distributed alpine snow simulations with snow transport against snow depths from Pléiades stereo imagery and snow melt-out dates from Sentinel-2 and Landsat-8 satellites. Additionally, we disentangle error contributions between blowing snow, precipitation heterogeneity, and unresolved subgrid variability. Snow transport enhances the snow simulations at high elevations, while precipitation biases are the main error source in other areas.

Surface dynamics and history of the calving cycle of Astrolabe Glacier (Adélie Coast, Antarctica) derived from satellite imagery

Surface dynamics and history of the calving cycle of Astrolabe Glacier (Adélie Coast, Antarctica) derived from satellite imagery Floriane Provost, Dimitri Zigone, Emmanuel Le Meur, Jean-Philippe Malet, and Clément Hibert The Cryosphere, 18, 3067–3079, https://doi.org/10.5194/tc-18-3067-2024, 2024 The recent calving of Astrolabe Glacier in November 2021 presents an opportunity to better understand the processes leading to ice fracturing. Optical-satellite imagery is used to retrieve the calving cycle of the glacier ice tongue and to measure the ice velocity and strain rates in order to document fracture evolution. We observed that the presence of sea ice for consecutive years has favoured the glacier extension but failed to inhibit the growth of fractures that accelerated in June 2021.

Suitability of the CICE sea ice model for seasonal prediction and positive impact of CryoSat-2 ice thickness initialization

Suitability of the CICE sea ice model for seasonal prediction and positive impact of CryoSat-2 ice thickness initialization Shan Sun and Amy Solomon The Cryosphere, 18, 3033–3048, https://doi.org/10.5194/tc-18-3033-2024, 2024 The study brings to light the suitability of CICE for seasonal prediction being contingent on several factors, such as initial conditions like sea ice coverage and thickness, as well as atmospheric and oceanic conditions including oceanic currents and sea surface temperature. We show there is potential to improve seasonal forecasting by using a more reliable sea ice thickness initialization. Thus, data assimilation of sea ice thickness is highly relevant for advancing seasonal prediction skills.

Assessing the key concerns in snow storage: a case study for China

Assessing the key concerns in snow storage: a case study for China Xing Wang, Feiteng Wang, Jiawen Ren, Dahe Qin, and Huilin Li The Cryosphere, 18, 3017–3031, https://doi.org/10.5194/tc-18-3017-2024, 2024 This work addresses snow storage at sports facilities in China. The snow pile at Big Air Shougang  (BAS) lost 158.6 m3 snow (6.7 %) during pre-competition and Winter Olympic competition days in winter 2022. There were no significant variations in the snow quality of the snow piles at BAS and the National Biathlon Center except for in the upper part of the snow piles. The 0.7 and 0.4 m thick cover layers protected half the snow height over the summer at Beijing and Chongli, respectively.

Arctic ice thinner near Canada; thicker elsewhere

The Arctic sea ice cover in June 2024 retreated at a below average pace, leading to a larger total sea ice extent for the month than in recent years. Many areas of open water have developed along the Arctic Ocean coast. … Continue reading →

Sea ice melt pond bathymetry reconstructed from aerial photographs using photogrammetry: a new method applied to MOSAiC data

Sea ice melt pond bathymetry reconstructed from aerial photographs using photogrammetry: a new method applied to MOSAiC data Niels Fuchs, Luisa von Albedyll, Gerit Birnbaum, Felix Linhardt, Natascha Oppelt, and Christian Haas The Cryosphere, 18, 2991–3015, https://doi.org/10.5194/tc-18-2991-2024, 2024 Melt ponds are key components of the Arctic sea ice system, yet methods to derive comprehensive pond depth data are missing. We present a shallow-water bathymetry retrieval to derive this elementary pond property at high spatial resolution from aerial images. The retrieval method is presented in a user-friendly way to facilitate replication. Furthermore, we provide pond properties on the MOSAiC expedition floe, giving insights into the three-dimensional pond evolution before and after drainage.

Effect of surficial geology mapping scale on modelled ground ice in Canadian Shield terrain

Effect of surficial geology mapping scale on modelled ground ice in Canadian Shield terrain H. Brendan O'Neill, Stephen A. Wolfe, Caroline Duchesne, and Ryan J. H. Parker The Cryosphere, 18, 2979–2990, https://doi.org/10.5194/tc-18-2979-2024, 2024 Maps that show ground ice in permafrost at circumpolar or hemispherical scales offer only general depictions of broad patterns in ice content. In this paper, we show that using more detailed surficial geology in a ground ice computer model significantly improves the depiction of ground ice and makes the mapping useful for assessments of the effects of permafrost thaw and for reconnaissance planning of infrastructure routing.

Antarctic ice shelves hold twice as much meltwater as previously thought

Slush -- water-soaked snow -- makes up more than half of all meltwater on the Antarctic ice shelves during the height of summer, yet is poorly accounted for in regional climate models. The findings could have profound implications for ice shelf stability and sea level rise.

Wildfires ravaging Arctic Circle - EU monitor

Scientists at the EU's Copernicus monitor say Russia's Sakha region is experiencing intense wildfires.

Freak event probably killed last woolly mammoths, scientists say

Study shows population on Arctic island was stable until sudden demise, countering theory of ‘genomic meltdown’

The last woolly mammoths on Earth took their final stand on a remote Arctic island about 4,000 years ago, but the question of what sealed their fate has remained a mystery. Now a genetic analysis suggests that a freak event such as an extreme storm or a plague was to blame.

The findings counter a previous theory that harmful genetic mutations caused by inbreeding led to a “genomic meltdown” in the isolated population. The latest analysis confirms that although the group had low genetic diversity, a stable population of a few hundred mammoths had occupied the island for thousands of years before suddenly vanishing.

Slushy surface of Antarctic ice shelves

Nature Geoscience, Published online: 27 June 2024; doi:10.1038/s41561-024-01445-x

Substantial contribution of slush to meltwater area across Antarctic ice shelves

Nature Geoscience, Published online: 27 June 2024; doi:10.1038/s41561-024-01466-6

Mapping geodetically inferred Antarctic ice surface height changes into thickness changes: a sensitivity study

Mapping geodetically inferred Antarctic ice surface height changes into thickness changes: a sensitivity study Natasha Valencic, Linda Pan, Konstantin Latychev, Natalya Gomez, Evelyn Powell, and Jerry X. Mitrovica The Cryosphere, 18, 2969–2978, https://doi.org/10.5194/tc-18-2969-2024, 2024 We quantify the effect of ongoing Antarctic bedrock uplift due to Ice Age or modern ice mass changes on estimates of ice thickness changes obtained from satellite-based ice height measurements. We find that variations in the Ice Age signal introduce an uncertainty in estimates of total Antarctic ice change of up to ~10%. Moreover, the usual assumption that the mapping between modern ice height and thickness changes is uniform systematically underestimates net Antarctic ice volume changes.

Multi-scale variations of subglacial hydro-mechanical conditions at Kongsvegen glacier, Svalbard

Multi-scale variations of subglacial hydro-mechanical conditions at Kongsvegen glacier, Svalbard Coline Bouchayer, Ugo Nanni, Pierre-Marie Lefeuvre, John Hult, Louise Steffensen Schmidt, Jack Kohler, François Renard, and Thomas V. Schuler The Cryosphere, 18, 2939–2968, https://doi.org/10.5194/tc-18-2939-2024, 2024 We explore the interplay between surface runoff and subglacial conditions. We focus on Kongsvegen glacier in Svalbard. We drilled 350 m down to the glacier base to measure water pressure, till strength, seismic noise, and glacier surface velocity. In the low-melt season, the drainage system adapted gradually, while the high-melt season led to a transient response, exceeding drainage capacity and enhancing sliding. Our findings contribute to discussions on subglacial hydro-mechanical processes.

Newly identified tipping point for ice sheets could mean greater sea level rise

Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say

A newly identified tipping point for the loss of ice sheets in Antarctica and elsewhere could mean future sea level rise is significantly higher than current projections.

A new study has examined how warming seawater intrudes between coastal ice sheets and the ground they rest on. The warm water melts cavities in the ice, allowing more water to flow in, expanding the cavities further in a feedback loop. This water then lubricates the collapse of ice into the ocean, pushing up sea levels.

Ice-shelf freshwater triggers for the Filchner–Ronne Ice Shelf melt tipping point in a global ocean–sea-ice model

Ice-shelf freshwater triggers for the Filchner–Ronne Ice Shelf melt tipping point in a global ocean–sea-ice model Matthew J. Hoffman, Carolyn Branecky Begeman, Xylar S. Asay-Davis, Darin Comeau, Alice Barthel, Stephen F. Price, and Jonathan D. Wolfe The Cryosphere, 18, 2917–2937, https://doi.org/10.5194/tc-18-2917-2024, 2024 The Filchner–Ronne Ice Shelf in Antarctica is susceptible to the intrusion of deep, warm ocean water that could increase the melting at the ice-shelf base by a factor of 10. We show that representing this potential melt regime switch in a low-resolution climate model requires careful treatment of iceberg melting and ocean mixing. We also demonstrate a possible ice-shelf melt domino effect where increased melting of nearby ice shelves can lead to the melt regime switch at Filchner–Ronne.

Daily briefing: ‘Polar rain aurora’ seen from Earth for the first time

Nature, Published online: 25 June 2024; doi:10.1038/d41586-024-02117-x

Tipping point in ice-sheet grounding-zone melting due to ocean water intrusion

Nature Geoscience, Published online: 25 June 2024; doi:10.1038/s41561-024-01465-7

Mystery of massive aurora in Arctic skies in December 2022 solved by astronomers

A small team of astronomers affiliated with several institutions in Japan, working with a pair of colleagues in the U.S., has solved the mystery of the unusually smooth aurora that appeared in the Arctic sky in December of 2022.

Three missing in Swiss floods as Alpine resort Zermatt cut off

Heavy rain and melting snow leaves Zermatt completely isolated.

The importance of cloud properties when assessing surface melting in an offline-coupled firn model over Ross Ice shelf, West Antarctica

The importance of cloud properties when assessing surface melting in an offline-coupled firn model over Ross Ice shelf, West Antarctica Nicolaj Hansen, Andrew Orr, Xun Zou, Fredrik Boberg, Thomas J. Bracegirdle, Ella Gilbert, Peter L. Langen, Matthew A. Lazzara, Ruth Mottram, Tony Phillips, Ruth Price, Sebastian B. Simonsen, and Stuart Webster The Cryosphere, 18, 2897–2916, https://doi.org/10.5194/tc-18-2897-2024, 2024 We investigated a melt event over the Ross Ice Shelf. We use regional climate models and a firn model to simulate the melt and compare the results with satellite data. We find that the firn model aligned well with observed melt days in certain parts of the ice shelf. The firn model had challenges accurately simulating the melt extent in the western sector. We identified potential reasons for these discrepancies, pointing to limitations in the models related to representing the cloud properties.

Exploring non-Gaussian sea ice characteristics via observing system simulation experiments

Exploring non-Gaussian sea ice characteristics via observing system simulation experiments Christopher Riedel and Jeffrey Anderson The Cryosphere, 18, 2875–2896, https://doi.org/10.5194/tc-18-2875-2024, 2024 Accurate sea ice conditions are crucial for quality sea ice projections, which have been connected to rapid warming over the Arctic. Knowing which observations to assimilate into models will help produce more accurate sea ice conditions. We found that not assimilating sea ice concentration led to more accurate sea ice states. The methods typically used to assimilate observations in our models apply assumptions to variables that are not well suited for sea ice because they are bounded variables.

Temporal markers in a temperate ice core: insights from 3H and 137Cs profiles from the Adamello Glacier

Temporal markers in a temperate ice core: insights from 3H and 137Cs profiles from the Adamello Glacier Elena Di Stefano, Giovanni Baccolo, Massimiliano Clemenza, Barbara Delmonte, Deborah Fiorini, Roberto Garzonio, Margit Schwikowski, and Valter Maggi The Cryosphere, 18, 2865–2874, https://doi.org/10.5194/tc-18-2865-2024, 2024 Rising temperatures are impacting the reliability of glaciers as environmental archives. This study reports how meltwater percolation affects the distribution of tritium and cesium, which are commonly used as temporal markers in dating ice cores, in a temperate glacier. Our findings challenge the established application of radionuclides for dating mountain ice cores and indicate tritium as the best choice.

Animal homosexual behaviour under-reported by scientists, survey shows

Study finds same-sex sexual behaviour in primates and other mammals widely observed but seldom published

George Murray Levick, an explorer with the Scott Antarctic expedition, spent the summer of 1911-12 taking detailed notes on the breeding cycle of Adélie penguins. Male penguins, he was surprised to discover, frequently had sex with other males, but this fact was deemed too shocking for inclusion in the official expedition report and it was another 50 years before it was noted in the scientific literature.

Today, same-sex sexual behaviours have been reported in a wide variety of species, but a new analysis suggests a gulf remains between how often it happens and how often we hear about it. A survey of animal scientists found they widely observe, yet seldom publish about, same-sex sexual behaviour in primates and other mammals.

Microstructure-based simulations of the viscous densification of snow and firn

Microstructure-based simulations of the viscous densification of snow and firn Kévin Fourteau, Johannes Freitag, Mika Malinen, and Henning Löwe The Cryosphere, 18, 2831–2846, https://doi.org/10.5194/tc-18-2831-2024, 2024 Understanding the settling of snow under its own weight has applications from avalanche forecasts to ice core interpretations. We study how this settling can be modeled using 3D images of the internal structure of snow and ice deformation mechanics. We found that classical ice mechanics, as used, for instance, in glacier flow, explain the compaction of dense polar snow but not that of lighter seasonal snow. How, exactly, the ice deforms during light snow compaction thus remains an open question.

Quantifying frost-weathering-induced damage in alpine rocks

Quantifying frost-weathering-induced damage in alpine rocks Till Mayer, Maxim Deprez, Laurenz Schröer, Veerle Cnudde, and Daniel Draebing The Cryosphere, 18, 2847–2864, https://doi.org/10.5194/tc-18-2847-2024, 2024 Frost weathering drives rockfall and shapes the evolution of alpine landscapes. We employed a novel combination of investigation techniques to assess the influence of different climatic conditions on high-alpine rock faces. Our results imply that rock walls exposed to freeze–thaw conditions, which are likely to occur at lower elevations, will weather more rapidly than rock walls exposed to sustained freezing conditions due to winter snow cover or permafrost at higher elevations.

Mapping and characterization of avalanches on mountain glaciers with Sentinel-1 satellite imagery

Mapping and characterization of avalanches on mountain glaciers with Sentinel-1 satellite imagery Marin Kneib, Amaury Dehecq, Fanny Brun, Fatima Karbou, Laurane Charrier, Silvan Leinss, Patrick Wagnon, and Fabien Maussion The Cryosphere, 18, 2809–2830, https://doi.org/10.5194/tc-18-2809-2024, 2024 Avalanches are important for the mass balance of mountain glaciers, but few data exist on where and when they occur and which glaciers they affect the most. We developed an approach to map avalanches over large glaciated areas and long periods of time using satellite radar data. The application of this method to various regions in the Alps and High Mountain Asia reveals the variability of avalanches on these glaciers and provides key data to better represent these processes in glacier models.

Impact of intercepted and sub-canopy snow microstructure on snowpack response to rain-on-snow events under a boreal canopy

Impact of intercepted and sub-canopy snow microstructure on snowpack response to rain-on-snow events under a boreal canopy Benjamin Bouchard, Daniel F. Nadeau, Florent Domine, Nander Wever, Adrien Michel, Michael Lehning, and Pierre-Erik Isabelle The Cryosphere, 18, 2783–2807, https://doi.org/10.5194/tc-18-2783-2024, 2024 Observations over several winters at two boreal sites in eastern Canada show that rain-on-snow (ROS) events lead to the formation of melt–freeze layers and that preferential flow is an important water transport mechanism in the sub-canopy snowpack. Simulations with SNOWPACK generally show good agreement with observations, except for the reproduction of melt–freeze layers. This was improved by simulating intercepted snow microstructure evolution, which also modulates ROS-induced runoff.

Subgridding high-resolution numerical weather forecast in the Canadian Selkirk mountain range for local snow modeling in a remote sensing perspective

Subgridding high-resolution numerical weather forecast in the Canadian Selkirk mountain range for local snow modeling in a remote sensing perspective Paul Billecocq, Alexandre Langlois, and Benoit Montpetit The Cryosphere, 18, 2765–2782, https://doi.org/10.5194/tc-18-2765-2024, 2024 Snow covers a vast part of the globe, making snow water equivalent (SWE) crucial for climate science and hydrology. SWE can be inversed from satellite data, but the snow's complex structure highly affects the signal, and thus an educated first guess is mandatory. In this study, a subgridding framework was developed to model snow at the local scale from model weather data. The framework enhanced snow parameter modeling, paving the way for SWE inversion algorithms from satellite data.

Glassy gels toughened by solvent

Nature, Published online: 19 June 2024; doi:10.1038/s41586-024-07564-0

Past and future of the Arctic sea ice in High-Resolution Model Intercomparison Project (HighResMIP) climate models

Past and future of the Arctic sea ice in High-Resolution Model Intercomparison Project (HighResMIP) climate models Julia Selivanova, Doroteaciro Iovino, and Francesco Cocetta The Cryosphere, 18, 2739–2763, https://doi.org/10.5194/tc-18-2739-2024, 2024 Climate models show differences in sea ice representation in comparison to observations. Increasing the model resolution is a recognized way to improve model realism and obtain more reliable future projections. We find no strong impact of resolution on sea ice representation; it rather depends on the analysed variable and the model used. By 2050, the marginal ice zone (MIZ) becomes a dominant feature of the Arctic ice cover, suggesting a shift to a new regime similar to that in Antarctica.

Will climate change turn the Arctic green?

Preparing ESA's Arctic Weather Satellite for liftoff

With ESA’s Arctic Weather Satellite due to launch in a few weeks, the satellite is now at the Vandenberg Space Force Base in California being readied for its big day. Once in orbit, this new mission will show how short-term weather forecasts in the Arctic and beyond could be improved.

Drones reveal Antarctic whale 'acrobatics'

Aerial footage of humpback whales shows how efficiently they can twist and turn their huge bodies.

Sensitivity to forecast surface mass balance outweighs sensitivity to basal sliding descriptions for 21st century mass loss from three major Greenland outlet glaciers

Sensitivity to forecast surface mass balance outweighs sensitivity to basal sliding descriptions for 21st century mass loss from three major Greenland outlet glaciers J. Rachel Carr, Emily A. Hill, and G. Hilmar Gudmundsson The Cryosphere, 18, 2719–2737, https://doi.org/10.5194/tc-18-2719-2024, 2024 The Greenland Ice Sheet is one of the world's largest glaciers and is melting quickly in response to climate change. It contains fast-flowing channels of ice that move ice from Greenland's centre to its coasts and allow Greenland to react quickly to climate warming. As a result, we want to predict how these glaciers will behave in the future, but there are lots of uncertainties. Here we assess the impacts of two main sources of uncertainties in glacier models.

Wreckage of Shackleton’s Last Ship Is Found Off Coast of Canada

Ernest Shackleton was sailing for Antarctica on the ship, called the Quest, when he died in 1922. Researchers exulted over the discovery of its wreckage, 62 years after it sank in the Labrador Sea.

If Paris Agreement Goals Are Missed, These Polar Bears Could Vanish

One group in Hudson Bay might have roughly decade left because sea ice is becoming too thin to support them as they hunt, according to new research.

How a single atomic sensor can help track Earth's glaciers

Earth observations are one of the most essential functions of our current fleet of satellites. Typically, each satellite specializes in one kind of remote sensing—monitoring ocean levels, for example, or watching clouds develop and move. That is primarily due to the constraints of their sensors—particularly the radar.

Eagle attacks, red invaders and a genetic bottleneck: inside the fight to save arctic foxes

Captive breeding in Norway has built up numbers endangered by the climate crisis and golden eagles but only a more diverse population will survive in the long term

Deep in the Norwegian mountains, amid a vast expanse of bright snow and howling winds, Toralf Mjøen throws a piece of meat into a fenced enclosure and waits for a pair of dark eyes to appear from the snowy den.

These curious and playful arctic foxes know Mjøen well. He has been the caretaker at this breeding facility for 17 years, going up the mountain daily to feed them at their enclosures near the small village of Oppdal, about 250 miles north of Oslo.

A mountainous mystery uncovered in Australia's pink sands

Deposits of deep-pink sand washing up on South Australian shores shed new light on when the Australian tectonic plate began to subduct beneath the Pacific plate, as well as the presence of previously unknown ancient Antarctic mountains.

Explorer Shackleton's last ship found on ocean floor

Wreck hunters find the ship on which famed polar explorer Ernest Shackleton made his final voyage.

Review article: Melt-affected ice cores for polar research in a warming world

Review article: Melt-affected ice cores for polar research in a warming world Dorothea Elisabeth Moser, Elizabeth R. Thomas, Christoph Nehrbass-Ahles, Anja Eichler, and Eric Wolff The Cryosphere, 18, 2691–2718, https://doi.org/10.5194/tc-18-2691-2024, 2024 Increasing temperatures worldwide lead to more melting of glaciers and ice caps, even in the polar regions. This is why ice-core scientists need to prepare to analyse records affected by melting and refreezing. In this paper, we present a summary of how near-surface melt forms, what structural imprints it leaves in snow, how various signatures used for ice-core climate reconstruction are altered, and how we can still extract valuable insights from melt-affected ice cores.

Fifty-year mystery of Mars' slow polar ice flow solved

Mars polar ice caps were one of the first Earth-like characteristics identified on Mars. Since the development of film in the 19th Century, researchers expected to see Earth-like activity, such as polar ice flow. Mars, however, doesn't follow expectations.

Two decades of deep ice cores from Antarctica

Nature, Published online: 10 June 2024; doi:10.1038/d41586-024-01507-5

Crossbows and eerie silences – following Antarctic whales for climate change clues

How scientists are discovering secrets of Antarctic climate change in the bodies of giant humpback whales.

New research finds lake under Mars ice cap unlikely

Cornell University researchers have provided a simple and comprehensive—if less dramatic—explanation for bright radar reflections initially interpreted as liquid water beneath the ice cap on Mars' south pole.

Weak relationship between remotely detected crevasses and inferred ice rheological parameters on Antarctic ice shelves

Weak relationship between remotely detected crevasses and inferred ice rheological parameters on Antarctic ice shelves Cristina Gerli, Sebastian Rosier, G. Hilmar Gudmundsson, and Sainan Sun The Cryosphere, 18, 2677–2689, https://doi.org/10.5194/tc-18-2677-2024, 2024 Recent efforts have focused on using AI and satellite imagery to track crevasses for assessing ice shelf damage and informing ice flow models. Our study reveals a weak connection between these observed products and damage maps inferred from ice flow models. While there is some improvement in crevasse-dense regions, this association remains limited. Directly mapping ice damage from satellite observations may not significantly improve the representation of these processes within ice flow models.

NASA satellite images of cyclones on Jupiter reveal storms are fueled by processes similar to those on Earth

New research led by Lia Siegelman, a physical oceanographer at UC San Diego's Scripps Institution of Oceanography, shows that the roiling storms at the planet Jupiter's polar regions are powered by processes known to physicists studying Earth's oceans and atmosphere. The geophysical commonalities spanning the 452 million miles between the two planets could even help facilitate an improved understanding of those processes on Earth.

Giant viruses found on Greenland ice sheet

Giant viruses found on the Greenland ice sheet probably regulate the growth of snow algae on the ice by infecting them. Knowing how to control these viruses could help us reduce the rate of ice-melt.

An early Hudson Bay opening

The sea ice cover in May 2024 was marked by an unusually early opening of eastern Hudson Bay. Overall, the rate of decline in the Arctic was near average for the month. In the Antarctic, the seasonal increase in ice … Continue reading →

Microscopic defects in ice shape how massive glaciers flow, study shows

A glacier's flow depends on how microscopic defects move through the ice, according to new research that also yielded a new model for predicting how glaciers will flow, ultimately contributing to sea-level rise.

Arctic melting heavily influenced by little-studied meteorological phenomena

A team of scientists has combined paleoclimatic data from the last 2,000 years with powerful computer modeling and in-the-field research on lake sediments and tree rings to show that an understudied phenomenon, known as atmospheric blocking, has long influenced temperature swings in the Arctic. As temperatures warm due to climate change, atmospheric blocking will help drive ever-wilder weather events. The study focused on the Norwegian Arctic archipelago, Svalbard, at the edge of the Arctic Ocean.

Thawing permafrost: Not a climate tipping element, but nevertheless far-reaching impacts

Permafrost soils store large quantities of organic carbon and are often portrayed as a critical tipping element in the Earth system, which, once global warming has reached a certain level, suddenly and globally collapses. Yet this image of a ticking timebomb, one that remains relatively quiet until, at a certain level of warming, it goes off, is a controversial one among the research community. Based on the scientific data currently available, the image is deceptive, as an international team has shown in a recently released study. According to their findings, there is no single global tipping point; rather, there are numerous local and regional ones, which 'tip' at different times, producing cumulative effects and causing the permafrost to thaw in step with climate change.

Coupled ice–ocean interactions during future retreat of West Antarctic ice streams in the Amundsen Sea sector

Coupled ice–ocean interactions during future retreat of West Antarctic ice streams in the Amundsen Sea sector David T. Bett, Alexander T. Bradley, C. Rosie Williams, Paul R. Holland, Robert J. Arthern, and Daniel N. Goldberg The Cryosphere, 18, 2653–2675, https://doi.org/10.5194/tc-18-2653-2024, 2024 A new ice–ocean model simulates future ice sheet evolution in the Amundsen Sea sector of Antarctica. Substantial ice retreat is simulated in all scenarios, with some retreat still occurring even with no future ocean melting. The future of small "pinning points" (islands of ice that contact the seabed) is an important control on this retreat. Ocean melting is crucial in causing these features to go afloat, providing the link by which climate change may affect this sector's sea level contribution.

No respite from permafrost-thaw impacts in the absence of a global tipping point

Nature Climate Change, Published online: 03 June 2024; doi:10.1038/s41558-024-02011-4

Estimating differential penetration of green (532 nm) laser light over sea ice with NASA's Airborne Topographic Mapper: observations and models

Estimating differential penetration of green (532 nm) laser light over sea ice with NASA's Airborne Topographic Mapper: observations and models Michael Studinger, Benjamin E. Smith, Nathan Kurtz, Alek Petty, Tyler Sutterley, and Rachel Tilling The Cryosphere, 18, 2625–2652, https://doi.org/10.5194/tc-18-2625-2024, 2024 We use green lidar data and natural-color imagery over sea ice to quantify elevation biases potentially impacting estimates of change in ice thickness of the polar regions. We complement our analysis using a model of scattering of light in snow and ice that predicts the shape of lidar waveforms reflecting from snow and ice surfaces based on the shape of the transmitted pulse. We find that biased elevations exist in airborne and spaceborne data products from green lidars.

Biases in ice sheet models from missing noise-induced drift

Biases in ice sheet models from missing noise-induced drift Alexander A. Robel, Vincent Verjans, and Aminat A. Ambelorun The Cryosphere, 18, 2613–2623, https://doi.org/10.5194/tc-18-2613-2024, 2024 The average size of many glaciers and ice sheets changes when noise is added to the system. The reasons for this drift in glacier state is intrinsic to the dynamics of how ice flows and the bumpiness of the Earth's surface. We argue that not including noise in projections of ice sheet evolution over coming decades and centuries is a pervasive source of bias in these computer models, and so realistic variability in glacier and climate processes must be included in models.

Historic iceberg surges offer insights on modern climate change

A great armada entered the North Atlantic, launched from the cold shores of North America. But rather than ships off to war, this force was a fleet of icebergs. And the havoc it wrought was to the ocean current itself. The future of the Atlantic circulation will be determined by a tug-o-war between Greenland's decreasing ice flux and its increasing freshwater runoff.

Local bright spot among melting glaciers: 2000 km of Antarctic ice-covered coastline has been stable for 85 years

A whaler's forgotten aerial photos from 1937 have given researchers the most detailed picture of the ice evolution in East Antarctica to date. The results show that the ice has remained stable and even grown slightly over almost a century, though scientists observe early signs of weakening. The research offers new insights that enhance predictions of ice changes and sea level rise.

Brief communication: Testing a portable Bullard-type temperature lance confirms highly spatially heterogeneous sediment temperatures under shallow bodies of water in the Arctic

Brief communication: Testing a portable Bullard-type temperature lance confirms highly spatially heterogeneous sediment temperatures under shallow bodies of water in the Arctic Frederieke Miesner, William Lambert Cable, Pier Paul Overduin, and Julia Boike The Cryosphere, 18, 2603–2611, https://doi.org/10.5194/tc-18-2603-2024, 2024 The temperature in the sediment below Arctic lakes determines the stability of the permafrost and microbial activity. However, measurements are scarce because of the remoteness. We present a robust and portable device to fill this gap. Test campaigns have demonstrated its utility in a range of environments during winter and summer. The measured temperatures show a great variability within and across locations. The data can be used to validate models and estimate potential emissions.

Responses of the Pine Island and Thwaites glaciers to melt and sliding parameterizations

Responses of the Pine Island and Thwaites glaciers to melt and sliding parameterizations Ian Joughin, Daniel Shapero, and Pierre Dutrieux The Cryosphere, 18, 2583–2601, https://doi.org/10.5194/tc-18-2583-2024, 2024 The Pine Island and Thwaites glaciers are losing ice to the ocean rapidly as warmer water melts their floating ice shelves. Models help determine how much such glaciers will contribute to sea level. We find that ice loss varies in response to how much melting the ice shelves are subjected to. Our estimated losses are also sensitive to how much the friction beneath the glaciers is reduced as it goes afloat. Melt-forced sea level rise from these glaciers is likely to be less than 10 cm by 2300.

Mapping surface hoar from near-infrared texture in a laboratory

Mapping surface hoar from near-infrared texture in a laboratory James Dillon, Christopher Donahue, Evan Schehrer, Karl Birkeland, and Kevin Hammonds The Cryosphere, 18, 2557–2582, https://doi.org/10.5194/tc-18-2557-2024, 2024 Surface hoar crystals are snow grains that form when vapor deposits on a snow surface. They create a weak layer in the snowpack that can cause large avalanches to occur. Thus, determining when and where surface hoar forms is a lifesaving matter. Here, we developed a means of mapping surface hoar using remote-sensing technologies. We found that surface hoar displayed heightened texture, hence the variability of brightness. Using this, we created surface hoar maps with an accuracy upwards of 95 %.

Sentinel-1 detection of ice slabs on the Greenland Ice Sheet

Sentinel-1 detection of ice slabs on the Greenland Ice Sheet Riley Culberg, Roger J. Michaelides, and Julie Z. Miller The Cryosphere, 18, 2531–2555, https://doi.org/10.5194/tc-18-2531-2024, 2024 Ice slabs enhance meltwater runoff from the Greenland Ice Sheet. Therefore, it is important to understand their extent and change in extent over time. We present a new method for detecting ice slabs in satellite radar data, which we use to map ice slabs at 500 m resolution across the entire ice sheet in winter 2016–2017. Our results provide better spatial coverage and resolution than previous maps from airborne radar and lay the groundwork for long-term monitoring of ice slabs from space.

Hydrological response of Andean catchments to recent glacier mass loss

Hydrological response of Andean catchments to recent glacier mass loss Alexis Caro, Thomas Condom, Antoine Rabatel, Nicolas Champollion, Nicolás García, and Freddy Saavedra The Cryosphere, 18, 2487–2507, https://doi.org/10.5194/tc-18-2487-2024, 2024 The glacier runoff changes are still unknown in most of the Andean catchments, thereby increasing uncertainties in estimating water availability, especially during the dry season. Here, we simulate glacier evolution and related glacier runoff changes across the Andes between 2000 and 2019. Our results indicate a glacier reduction in 93 % of the catchments, leading to a 12 % increase in glacier melt. These results can be downloaded and integrated with discharge measurements in each catchment.

Assessment of the impact of dam reservoirs on river ice cover – an example from the Carpathians (central Europe)

Assessment of the impact of dam reservoirs on river ice cover – an example from the Carpathians (central Europe) Maksymilian Fukś The Cryosphere, 18, 2509–2529, https://doi.org/10.5194/tc-18-2509-2024, 2024 This paper presents a method for determining the impact of dam reservoirs on the occurrence of ice cover on rivers downstream of their location. It was found that the operation of dam reservoirs reduces the duration of ice cover and significantly affects the ice regime of rivers. Based on the results presented, it can be assumed that dam reservoirs play an important role in transforming ice conditions on rivers.

Estimating the uncertainty of sea-ice area and sea-ice extent from satellite retrievals

Estimating the uncertainty of sea-ice area and sea-ice extent from satellite retrievals Andreas Wernecke, Dirk Notz, Stefan Kern, and Thomas Lavergne The Cryosphere, 18, 2473–2486, https://doi.org/10.5194/tc-18-2473-2024, 2024 The total Arctic sea-ice area (SIA), which is an important climate indicator, is routinely monitored with the help of satellite measurements. Uncertainties in observations of sea-ice concentration (SIC) partly cancel out when summed up to the total SIA, but the degree to which this is happening has been unclear. Here we find that the uncertainty daily SIA estimates, based on uncertainties in SIC, are about 300 000 km2. The 2002 to 2017 September decline in SIA is approx. 105 000 ± 9000 km2 a−1.

Mapping the vertical heterogeneity of Greenland's firn from 2011–2019 using airborne radar and laser altimetry

Mapping the vertical heterogeneity of Greenland's firn from 2011–2019 using airborne radar and laser altimetry Anja Rutishauser, Kirk M. Scanlan, Baptiste Vandecrux, Nanna B. Karlsson, Nicolas Jullien, Andreas P. Ahlstrøm, Robert S. Fausto, and Penelope How The Cryosphere, 18, 2455–2472, https://doi.org/10.5194/tc-18-2455-2024, 2024 The Greenland Ice Sheet interior is covered by a layer of firn, which is important for surface meltwater runoff and contributions to global sea-level rise. Here, we combine airborne radar sounding and laser altimetry measurements to delineate vertically homogeneous and heterogeneous firn. Our results reveal changes in firn between 2011–2019, aligning well with known climatic events. This approach can be used to outline firn areas primed for significantly changing future meltwater runoff.

Geothermal heat source estimations through ice flow modelling at Mýrdalsjökull, Iceland

Geothermal heat source estimations through ice flow modelling at Mýrdalsjökull, Iceland Alexander H. Jarosch, Eyjólfur Magnússon, Krista Hannesdóttir, Joaquín M. C. Belart, and Finnur Pálsson The Cryosphere, 18, 2443–2454, https://doi.org/10.5194/tc-18-2443-2024, 2024 Geothermally active regions beneath glaciers not only influence local ice flow as well as the mass balance of glaciers but also control changes of subglacial water reservoirs and possible subsequent glacier lake outburst floods. In Iceland, such outburst floods impose danger to people and infrastructure and are therefore monitored. We present a novel computer-simulation-supported method to estimate the activity of such geothermal areas and to monitor its evolution.

Reconstructing dynamics of the Baltic Ice Stream Complex during deglaciation of the Last Scandinavian Ice Sheet

Reconstructing dynamics of the Baltic Ice Stream Complex during deglaciation of the Last Scandinavian Ice Sheet Izabela Szuman, Jakub Z. Kalita, Christiaan R. Diemont, Stephen J. Livingstone, Chris D. Clark, and Martin Margold The Cryosphere, 18, 2407–2428, https://doi.org/10.5194/tc-18-2407-2024, 2024 A Baltic-wide glacial landform-based map is presented, filling in a geographical gap in the record that has been speculated about by palaeoglaciologists for over a century. Here we used newly available bathymetric data and provide landform evidence of corridors of fast ice flow that we interpret as ice streams. Where previous ice-sheet-scale investigations inferred a single ice source, our mapping identifies flow and ice margin geometries from both Swedish and Bothnian sources.

A large-scale high-resolution numerical model for sea-ice fragmentation dynamics

A large-scale high-resolution numerical model for sea-ice fragmentation dynamics Jan Åström, Fredrik Robertsen, Jari Haapala, Arttu Polojärvi, Rivo Uiboupin, and Ilja Maljutenko The Cryosphere, 18, 2429–2442, https://doi.org/10.5194/tc-18-2429-2024, 2024 The HiDEM code has been developed for analyzing the fracture and fragmentation of brittle materials and has been extensively applied to glacier calving. Here, we report on the adaptation of the code to sea-ice dynamics and breakup. The code demonstrates the capability to simulate sea-ice dynamics on a 100 km scale with an unprecedented resolution. We argue that codes of this type may become useful for improving forecasts of sea-ice dynamics.

Multivariate state and parameter estimation with data assimilation applied to sea-ice models using a Maxwell elasto-brittle rheology

Multivariate state and parameter estimation with data assimilation applied to sea-ice models using a Maxwell elasto-brittle rheology Yumeng Chen, Polly Smith, Alberto Carrassi, Ivo Pasmans, Laurent Bertino, Marc Bocquet, Tobias Sebastian Finn, Pierre Rampal, and Véronique Dansereau The Cryosphere, 18, 2381–2406, https://doi.org/10.5194/tc-18-2381-2024, 2024 We explore multivariate state and parameter estimation using a data assimilation approach through idealised simulations in a dynamics-only sea-ice model based on novel rheology. We identify various potential issues that can arise in complex operational sea-ice models when model parameters are estimated. Even though further investigation will be needed for such complex sea-ice models, we show possibilities of improving the observed and the unobserved model state forecast and parameter accuracy.

The role of upper-ocean heat content in the regional variability of Arctic sea ice at sub-seasonal timescales

The role of upper-ocean heat content in the regional variability of Arctic sea ice at sub-seasonal timescales Elena Bianco, Doroteaciro Iovino, Simona Masina, Stefano Materia, and Paolo Ruggieri The Cryosphere, 18, 2357–2379, https://doi.org/10.5194/tc-18-2357-2024, 2024 Changes in ocean heat transport and surface heat fluxes in recent decades have altered the Arctic Ocean heat budget and caused warming of the upper ocean. Using two eddy-permitting ocean reanalyses, we show that this has important implications for sea ice variability. In the Arctic regional seas, upper-ocean heat content acts as an important precursor for sea ice anomalies on sub-seasonal timescales, and this link has strengthened since the 2000s.

A climate-driven, altitudinal transition in rock glacier dynamics detected through integration of geomorphological mapping and synthetic aperture radar interferometry (InSAR)-based kinematics

A climate-driven, altitudinal transition in rock glacier dynamics detected through integration of geomorphological mapping and synthetic aperture radar interferometry (InSAR)-based kinematics Aldo Bertone, Nina Jones, Volkmar Mair, Riccardo Scotti, Tazio Strozzi, and Francesco Brardinoni The Cryosphere, 18, 2335–2356, https://doi.org/10.5194/tc-18-2335-2024, 2024 Traditional inventories display high uncertainty in discriminating between intact (permafrost-bearing) and relict (devoid) rock glaciers (RGs). Integration of InSAR-based kinematics in South Tyrol affords uncertainty reduction and depicts a broad elevation belt of relict–intact coexistence. RG velocity and moving area (MA) cover increase linearly with elevation up to an inflection at 2600–2800 m a.s.l., which we regard as a signature of sporadic-to-discontinuous permafrost transition.

Western Arctic leads the way on springtime decline

April sea ice loss in the Arctic proceeded at a near-average rate overall, with the majority of ice losses in the Bering Sea and Sea of Okhotsk. In the Antarctic, sea ice grew faster than average, roughly evenly around the … Continue reading →

Insights into glacial processes from micromorphology of silt-sized sediment

Insights into glacial processes from micromorphology of silt-sized sediment Allison P. Lepp, Lauren E. Miller, John B. Anderson, Matt O'Regan, Monica C. M. Winsborrow, James A. Smith, Claus-Dieter Hillenbrand, Julia S. Wellner, Lindsay O. Prothro, and Evgeny A. Podolskiy The Cryosphere, 18, 2297–2319, https://doi.org/10.5194/tc-18-2297-2024, 2024 Shape and surface texture of silt-sized grains are measured to connect marine sediment records with subglacial water flow. We find that grain shape alteration is greatest in glaciers where high-energy drainage events and abundant melting of surface ice are inferred and that the surfaces of silt-sized sediments preserve evidence of glacial transport. Our results suggest grain shape and texture may reveal whether glaciers previously experienced temperate conditions with more abundant meltwater.

Thermal infrared shadow-hiding in GOES-R ABI imagery: snow and forest temperature observations from the SnowEx 2020 Grand Mesa field campaign

Thermal infrared shadow-hiding in GOES-R ABI imagery: snow and forest temperature observations from the SnowEx 2020 Grand Mesa field campaign Steven J. Pestana, C. Chris Chickadel, and Jessica D. Lundquist The Cryosphere, 18, 2257–2276, https://doi.org/10.5194/tc-18-2257-2024, 2024 We compared infrared images taken by GOES-R satellites of an area with snow and forests against surface temperature measurements taken on the ground, from an aircraft, and by another satellite. We found that GOES-R measured warmer temperatures than the other measurements, especially in areas with more forest and when the Sun was behind the satellite. From this work, we learned that the position of the Sun and surface features such as trees that can cast shadows impact GOES-R infrared images.

Arctic sea ice: Walking on sunshine

Following the 2024 maximum sea ice extent on March 14, Arctic ice extent has declined slowly such that 2024 March average is the fifteenth lowest in the passive microwave satellite record. The atmospheric circulation pattern for March 2024 featured a strong … Continue reading →

Subglacial valleys preserved in the highlands of south and east Greenland record restricted ice extent during past warmer climates

Subglacial valleys preserved in the highlands of south and east Greenland record restricted ice extent during past warmer climates Guy J. G. Paxman, Stewart S. R. Jamieson, Aisling M. Dolan, and Michael J. Bentley The Cryosphere, 18, 1467–1493, https://doi.org/10.5194/tc-18-1467-2024, 2024 This study uses airborne radar data and satellite imagery to map mountainous topography hidden beneath the Greenland Ice Sheet. We find that the landscape records the former extent and configuration of ice masses that were restricted to areas of high topography. Computer models of ice flow indicate that valley glaciers eroded this landscape millions of years ago when local air temperatures were at least 4 °C higher than today and Greenland’s ice volume was

Retrieval of sea ice drift in the Fram Strait based on data from Chinese satellite HaiYang (HY-1D)

Retrieval of sea ice drift in the Fram Strait based on data from Chinese satellite HaiYang (HY-1D) Dunwang Lu, Jianqiang Liu, Lijian Shi, Tao Zeng, Bin Cheng, Suhui Wu, and Manman Wang The Cryosphere, 18, 1419–1441, https://doi.org/10.5194/tc-18-1419-2024, 2024 We retrieved sea ice drift in Fram Strait using the Chinese HaiYang 1D Coastal Zone Imager. The dataset is has hourly and daily intervals for analysis, and validation is performed using a synthetic aperture radar (SAR)-based product and International Arctic Buoy Programme (IABP)  buoys. The differences between them are explained by investigating the spatiotemporal variability in sea ice motion. The accuracy of flow direction retrieval for sea ice drift is also related to sea ice displacement.

Review article: Terrestrial dissolved organic carbon in northern permafrost

Review article: Terrestrial dissolved organic carbon in northern permafrost Liam Heffernan, Dolly N. Kothawala, and Lars J. Tranvik The Cryosphere, 18, 1443–1465, https://doi.org/10.5194/tc-18-1443-2024, 2024 The northern permafrost region stores half the world's soil carbon. As the region warms, permafrost thaws and releases dissolved organic carbon, which leads to decomposition of this carbon pool or export into aquatic ecosystems. In this study we developed a new database of 2276 dissolved organic carbon concentrations in eight different ecosystems from 111 studies published over 22 years. This study highlights that coastal areas may play an important role in future high-latitude carbon cycling.

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica's ice sheets. An international research team has now used sediments taken from the South Pacific to reconstruct the flow speed in the last 5.3 million years. Their data show that during glacial periods, the current slowed; during interglacials, it accelerated. Consequently, if the current global warming intensifies in the future, it could mean that the Southern Ocean stores less CO2 and that more heat reaches Antarctica.

Sea-ice variations and trends during the Common Era in the Atlantic sector of the Arctic Ocean

Sea-ice variations and trends during the Common Era in the Atlantic sector of the Arctic Ocean Ana Lúcia Lindroth Dauner, Frederik Schenk, Katherine Elizabeth Power, and Maija Heikkilä The Cryosphere, 18, 1399–1418, https://doi.org/10.5194/tc-18-1399-2024, 2024 In this study, we analysed 14 sea-ice proxy records and compared them with the results from two different climate simulations from the Atlantic sector of the Arctic Ocean over the Common Era (last 2000 years). Both proxy and model approaches demonstrated a long-term sea-ice increase. The good correspondence suggests that the state-of-the-art sea-ice proxies are able to capture large-scale climate drivers. Short-term variability, however, was less coherent due to local-to-regional scale forcings.

Melting ice solves leap-second problem — for now

Nature, Published online: 27 March 2024; doi:10.1038/d41586-024-00850-x

How climate change is affecting global timekeeping

Nature, Published online: 27 March 2024; doi:10.1038/d41586-024-00952-6

Climate change has slowed Earth’s rotation — and could affect how we keep time

Nature, Published online: 27 March 2024; doi:10.1038/d41586-024-00932-w

Five million years of Antarctic Circumpolar Current strength variability

Nature, Published online: 27 March 2024; doi:10.1038/s41586-024-07143-3

A global timekeeping problem postponed by global warming

Nature, Published online: 27 March 2024; doi:10.1038/s41586-024-07170-0

Scientists on the hunt for evidence of quantum gravity's existence at the South Pole

An Antarctic large-scale experiment is striving to find out if gravity also exists at the quantum level. An extraordinary particle able to travel undisturbed through space seems to hold the answer.

Modeling the timing of Patagonian Ice Sheet retreat in the Chilean Lake District from 22–10 ka

Modeling the timing of Patagonian Ice Sheet retreat in the Chilean Lake District from 22–10 ka Joshua Cuzzone, Matias Romero, and Shaun A. Marcott The Cryosphere, 18, 1381–1398, https://doi.org/10.5194/tc-18-1381-2024, 2024 We simulate the retreat history of the Patagonian Ice Sheet (PIS) across the Chilean Lake District from 22–10 ka. These results improve our understanding of the response of the PIS to deglacial warming and the patterns of deglacial ice margin retreat where gaps in the geologic record still exist, and they indicate that changes in large-scale precipitation during the last deglaciation played an important role in modulating the response of ice margin change across the PIS to deglacial warming.

Snow mechanical property variability at the slope scale – implication for snow mechanical modelling

Snow mechanical property variability at the slope scale – implication for snow mechanical modelling Francis Meloche, Francis Gauthier, and Alexandre Langlois The Cryosphere, 18, 1359–1380, https://doi.org/10.5194/tc-18-1359-2024, 2024 Snow avalanches are a dangerous natural hazard. Backcountry recreationists and avalanche practitioners try to predict avalanche hazard based on the stability of snow cover. However, snow cover is variable in space, and snow stability observations can vary within several meters. We measure the snow stability several times on a small slope to create high-resolution maps of snow cover stability. These results help us to understand the snow variation for scientists and practitioners.

Arctic sea ice reaches a below-average maximum

Arctic sea ice has likely reached its maximum extent for the year, at 15.01 million square kilometers (5.80 million square miles) on March 14. The 2024 maximum is the fourteenth lowest in the 46-year satellite record. Overview of conditions On … Continue reading →

Northern lights predicted in US and UK on Monday night in wake of solar storms

Spectacular aurora borealis caused by geomagnetic storms on sun’s surface may be visible in North America as far south as the midwest

Solar eruptions are sending a stream of particles towards Earth, creating spectacular auroras in both hemispheres.

The aurora borealis – in the northern hemisphere – will be potentially visible on Monday night in the US as far south as the midwest. The northern lights, more commonly seen within the Arctic Circle, could also be visible in Scotland.

A friendship dating back to teenage years is one to treasure, especially during a crisis

It’s not easy to maintain the closeness of relationships of our youth but Abigail Dean will always make time for the friend she grew up with

In early 2006, when I was 17, I was admitted to a well-known psychiatric hospital in the UK, an institution most associated with models and footballers. I was neither. I was a schoolgirl who had suffered from either a chemical imbalance in the brain or a series of poor life decisions, depending on who you asked. For two months I was to live in a small pink room with immovable furniture, and attend every therapy on offer. I revised for my AS Levels in the communal lounge while people watched television or wept over the evening meal.

On my first day there, snow fell furiously across Derbyshire. My parents live on a big hill in a small village, and were snow-bound. Visiting hours inched around. I resigned myself to two hours of self-pity, listening to the hum of reunions from the surrounding rooms. But 30 minutes before the doors closed, in walked my friend, Ruth, who had got her driving licence just the month before. She was carrying a week’s supply of the worst gossip magazines of the late noughties and a craft kit for homemade cards. I would not spend the evening alone.

Enormous ice loss from Greenland glacier

Ground-based measuring devices and aircraft radar operated in the far northeast of Greenland show how much ice the 79 N-Glacier is losing. According to recent measurements, the thickness of the glacier has decreased by more than 160 meters since 1998. Warm ocean water flowing under the glacier tongue is melting the ice from below. High air temperatures cause lakes to form on the surface, whose water flows through huge channels in the ice into the ocean. One channel reached a height of 500 meters, while the ice above was only 190 meters thick.

Extreme melting at Greenland's largest floating ice tongue

Extreme melting at Greenland's largest floating ice tongue Ole Zeising, Niklas Neckel, Nils Dörr, Veit Helm, Daniel Steinhage, Ralph Timmermann, and Angelika Humbert The Cryosphere, 18, 1333–1357, https://doi.org/10.5194/tc-18-1333-2024, 2024 The 79° North Glacier in Greenland has experienced significant changes over the last decades. Due to extreme melt rates, the ice has thinned significantly in the vicinity of the grounding line, where a large subglacial channel has formed since 2010. We attribute these changes to warm ocean currents and increased subglacial discharge from surface melt. However, basal melting has decreased since 2018, indicating colder water inflow into the cavity below the glacier.

Out of Eden Walk: Walking to the Holy Land

It was in the ancient city of Petra, in 2013, when National Geographic Explorer Paul Salopek said he came upon a crossroad filled with antiquity, fabulous monuments, palaces and grand avenues chiseled into a sandstone canyon far above the rift valley of Jordan. 

After walking for the better part of a year through the desolate deserts of the Horn of Africa and then into the almost equally desert and empty landscape of Saudi Arabia, Salopek said he was welcomed into  Jordan by a Bedouin musician named Qasim Ali.

Qasim Ali sings the blues, Bedouin style, at Petra, the ancient heart of the Nabatean empire. Join the journey at outofedenwalk.org.

Credit:

Paul Salopek/National Geographic

Ali sang the blues while playing the Rababa, an ancient stringed instrument. Salopek described it as a dramatic setting.

“It kind of became the backdrop music for stepping from nomadism into millennia of settlement, into this highly contested, many-chambered heart that we call the Levant,” he said.

The World’s Marco Werman talked more with Salopek about his journey through Jordan and into the Israeli-occupied West Bank, following in the footsteps of the first humans out of Africa. 

Ghawarna women dye wool using oxide-rich mud. Modaita, the yawning camel is unimpressed. Join the journey at outofedenwalk.org. 

Credit:

Paul Salopek/National Geographic

Bullet on the road to Bethlehem. Join the journey at outofedenwalk.org. 

Credit:

Paul Salopek/National Geographic

In Bethlehem, the Church of the Nativity. Join the journey at outofedenwalk.org. 

Credit:

Paul Salopek/National Geographic

Yuval Ben-Ami at the Separation Barrier in East Jerusalem. Erected by the Israeli government to thwart terror attacks, it cleaves some Palestinian neighborhoods in half. Join the journey at outofedenwalk.org. 

Credit:

Paul Salopek/National Geographic

Parts of this interview have been lightly edited for length and clarity.Writer and National Geographic Explorer Paul Salopek has embarked on a 24,000-mile storytelling trek across the world called the “Out of Eden Walk.” The National Geographic Society, committed to illuminating and protecting the wonder of our world, has funded Salopek and the project since 2013. Explore the project here. Follow the journey on X at @PaulSalopek, @outofedenwalk and also at @InsideNatGeo.

New geological study: Scandinavia was born in Greenland

The oldest Scandinavian bedrock was 'born' in Greenland, according to a new geological study. The study helps us understand the origin of continents and why Earth is the only planet in our solar system with life.

Media invitation: Last chance to see Arctic Weather Satellite

Call for media: Last chance to see Arctic Weather Satellite

Fjord circulation induced by melting icebergs

Fjord circulation induced by melting icebergs Kenneth G. Hughes The Cryosphere, 18, 1315–1332, https://doi.org/10.5194/tc-18-1315-2024, 2024 A mathematical and conceptual model of how the melting of hundreds of icebergs generates currents within a fjord.

US and Germany partnering on mission to track Earth's water movement

NASA and the German Space Agency at DLR (German Aerospace Center) have agreed to jointly build, launch, and operate a pair of spacecraft that will yield insights into how Earth's water, ice, and land masses are shifting by measuring monthly changes in the planet's gravity field. Tracking large-scale mass changes—showing when and where water moves within and between the atmosphere, oceans, underground aquifers, and ice sheets—provides a view into Earth's water cycle, including changes in response to drivers like climate change.

Understanding snow saltation parameterizations: lessons from theory, experiments and numerical simulations

Understanding snow saltation parameterizations: lessons from theory, experiments and numerical simulations Daniela Brito Melo, Armin Sigmund, and Michael Lehning The Cryosphere, 18, 1287–1313, https://doi.org/10.5194/tc-18-1287-2024, 2024 Snow saltation – the transport of snow close to the surface – occurs when the wind blows over a snow-covered surface with sufficient strength. This phenomenon is represented in some climate models; however, with limited accuracy. By performing numerical simulations and a detailed analysis of previous works, we show that snow saltation is characterized by two regimes. This is not represented in climate models in a consistent way, which hinders the quantification of snow transport and sublimation.

Plantwatch: how does moss survive and thrive in harsh Antarctic climate?

Incredibly tough plants can tolerate intense cold and prolonged darkness, but temperature has also been rising

Mosses are the plant superheroes of Antarctica, steadily colonising parts of the continent, building up into plump green cushions or even deep banks on bare ground, some of it newly exposed by melting ice and snow.

These are incredibly tough plants that only grow slowly in the harsh Antarctic climate, tolerating intense cold, prolonged dryness, powerful ultraviolet light and prolonged winter darkness. They often survive for nine to 10 months dormant under winter snow, using their own antifreeze to prevent their cells icing up. In their brief growing season, the mosses thaw out, soak up water like sponges and spring back to life. They can even withstand being buried under glaciers for centuries. One moss was found to be 1,530 years old; trapped in ice, it resurrected itself after thawing out.

Watch US soldiers parachute onto polar landscape

The military exercise named Arctic Shock is part of cold-weather field training with the Norwegian Army.

Lead fractions from SAR-derived sea ice divergence during MOSAiC

Lead fractions from SAR-derived sea ice divergence during MOSAiC Luisa von Albedyll, Stefan Hendricks, Nils Hutter, Dmitrii Murashkin, Lars Kaleschke, Sascha Willmes, Linda Thielke, Xiangshan Tian-Kunze, Gunnar Spreen, and Christian Haas The Cryosphere, 18, 1259–1285, https://doi.org/10.5194/tc-18-1259-2024, 2024 Leads (openings in sea ice cover) are created by sea ice dynamics. Because they are important for many processes in the Arctic winter climate, we aim to detect them with satellites. We present two new techniques to detect lead widths of a few hundred meters at high spatial resolution (700 m) and independent of clouds or sun illumination. We use the MOSAiC drift 2019–2020 in the Arctic for our case study and compare our new products to other existing lead products.

Deep clustering in subglacial radar reflectance reveals subglacial lakes

Deep clustering in subglacial radar reflectance reveals subglacial lakes Sheng Dong, Lei Fu, Xueyuan Tang, Zefeng Li, and Xiaofei Chen The Cryosphere, 18, 1241–1257, https://doi.org/10.5194/tc-18-1241-2024, 2024 Subglacial lakes are a unique environment at the bottom of ice sheets, and they have distinct features in radar echo images that allow for visual detection. In this study, we use machine learning to analyze radar reflection waveforms and identify candidate subglacial lakes. Our approach detects more lakes than known inventories and can be used to expand the subglacial lake inventory. Additionally, this analysis may also provide insights into interpreting other subglacial conditions.

Scientists in Antarctica track ‘baffling’ virus that could decimate penguins and other polar animals

The flu strain has killed few seabirds on southern continent so far, but there is grave concern for the next breeding season

Self-heating concrete is one step closer to putting snow shovels and salt out of business

Researchers recently reported on the science behind its special concrete, that can warm itself up when it snows, or as temperatures approach freezing.

The 'insane' plan to save the Arctic's sea-ice

Could a daring experiment help our planet or is it a dangerous distraction?

Oregon State researchers take deep dive into how much water is stored in snow

There's a new metric that provides a more holistic look at how much water is stored in snowpack, and for how long.

Meteorology: Weak polar vortex makes weather more predictable

Events in the stratosphere are making long-range weather in Northern Europe easier to forecast, researchers have discovered.

Arctic nightlife: Seabird colony bursts with sound at night

Acoustic recordings of a colony of little auks reveal their nocturnal activities and offer valuable monitoring means for avian biology in the Arctic.

Bird-flu threat disrupts Antarctic penguin studies

Nature, Published online: 15 March 2024; doi:10.1038/d41586-024-00807-0

Arctic Weather Satellite tested for life in orbit

ESA's Arctic Weather Satellite has passed its environmental test campaign with flying colors—meaning that the satellite has been declared fit for liftoff and its life in the harsh environment of space.

‘Cold blob’ of Arctic meltwater may be causing European heat waves

Study identifies chain of events linking Arctic warming and extreme European weather

Arctic Weather Satellite tested for life in orbit

ESA’s Arctic Weather Satellite has passed its environmental test campaign with flying colours – meaning that the satellite has been declared fit for liftoff and its life in the harsh environment of space.

This new satellite, which is slated for launch in June, has been designed to show how it can improve weather forecasts in the Arctic – a region that currently lacks data for accurate short-term forecasts.

Melt rate of Greenland ice sheet can predict summer weather in Europe, scientist says

Location, extent and strength of recent freshwater events suggest an unusually warm and dry summer over southern Europe this year

Long-range weather predictions are notoriously difficult, but a new paper in the journal Weather and Climate Dynamics suggests that the melt rate of the Greenland ice sheet can predict the next summer’s weather in Europe.

The chain of events is complex and other factors may interfere. But according to Dr Marilena Oltmanns of the UK National Oceanography Centre, lead author of the study, it goes roughly as follows:

The future is likely less skiable, thanks to climate change

Annual snow cover days in all major skiing regions are projected to decrease dramatically as a result of climate change, with 1 in 8 ski areas losing all natural snow cover this century under high emission scenarios, according to a new study.

Wim Hof breathing and cold-exposure method may have benefits, study finds

Adrenaline release thought to dampen inflammation, but experts say method ‘not without risks’

Whether plunging themselves into ice baths or deliberately hyperventilating and then holding their breath, devotees of “The Iceman” Wim Hof are evangelical about the physical and mental benefits these practices bring. A new study suggests they may indeed reduce levels of inflammation in the body. However, experts stress that practising the Wim Hof method is not without risk.

Hof is a Dutch athlete, best known for record-breaking feats such as swimming under ice and running barefoot on ice and snow. More recently, he has built a business empire on the techniques he uses – which focus on a commitment mastering conscious breathing and cold exposure – with courses available around the world.

High resolution imagery advances the ability to monitor decadal changes in emperor penguin populations

Emperor penguin populations have been exceedingly difficult to monitor because of their remote locations, and because individuals form breeding colonies on seasonal sea ice fastened to land (known as fast ice) during the dark and cold Antarctic winter. New research that incorporates very high-resolution satellite imagery with field-based validation surveys and long-term data has provided the first multi-year time series that documents emperor penguin global population trends.

Grounding zone discovery explains accelerated melting under Greenland's glaciers

Researchers have conducted the first large-scale observation and modeling study of northwest Greenland's Petermann Glacier. Their findings reveal the intrusion of warm ocean water beneath the ice as the culprit in the accelerated melting it has experienced since the turn of the century, and their computer predictions indicate that potential sea level rise will be much worse than previously estimated.

Giant volcano discovered on Mars

In a groundbreaking announcement at the 55th Lunar and Planetary Science Conference held in The Woodlands, Texas, scientists revealed the discovery of a giant volcano and possible sheet of buried glacier ice in the eastern part of Mars' Tharsis volcanic province near the planet's equator.

Exploring arctic plants and lichens: An important conservation baseline for Nunavut's newest and largest territorial park

A comprehensive study of the floristic diversity of Agguttinni Territorial Park, Nunavut's newest and largest Territorial Park, has documented 141 vascular plant, 69 bryophyte, and 93 lichen species from this unique protected area on northern Baffin Island. Through a combination of extensive fieldwork in 2021 and examination of hundreds of existing herbarium specimens, the authors have documented species newly reported for Baffin Island and have crafted a biodiversity baseline important for park management and conservation.

Observations and modeling of areal surface albedo and surface types in the Arctic

Observations and modeling of areal surface albedo and surface types in the Arctic Evelyn Jäkel, Sebastian Becker, Tim R. Sperzel, Hannah Niehaus, Gunnar Spreen, Ran Tao, Marcel Nicolaus, Wolfgang Dorn, Annette Rinke, Jörg Brauchle, and Manfred Wendisch The Cryosphere, 18, 1185–1205, https://doi.org/10.5194/tc-18-1185-2024, 2024 The results of the surface albedo scheme of a coupled regional climate model were evaluated against airborne and ground-based measurements conducted in the European Arctic in different seasons between 2017 and 2022. We found a seasonally dependent bias between measured and modeled surface albedo for cloudless and cloudy situations. The strongest effects of the albedo model bias on the net irradiance were most apparent in the presence of optically thin clouds.

Understanding the influence of ocean waves on Arctic sea ice simulation: a modeling study with an atmosphere–ocean–wave–sea ice coupled model

Understanding the influence of ocean waves on Arctic sea ice simulation: a modeling study with an atmosphere–ocean–wave–sea ice coupled model Chao-Yuan Yang, Jiping Liu, and Dake Chen The Cryosphere, 18, 1215–1239, https://doi.org/10.5194/tc-18-1215-2024, 2024 We present a new atmosphere–ocean–wave–sea ice coupled model to study the influences of ocean waves on Arctic sea ice simulation. Our results show (1) smaller ice-floe size with wave breaking increases ice melt, (2) the responses in the atmosphere and ocean to smaller floe size partially reduce the effect of the enhanced ice melt, (3) the limited oceanic energy is a strong constraint for ice melt enhancement, and (4) ocean waves can indirectly affect sea ice through the atmosphere and the ocean.

Brief communication: Significant biases in ERA5 output for the McMurdo Dry Valleys region, Antarctica

Brief communication: Significant biases in ERA5 output for the McMurdo Dry Valleys region, Antarctica Ricardo Garza-Girón and Slawek M. Tulaczyk The Cryosphere, 18, 1207–1213, https://doi.org/10.5194/tc-18-1207-2024, 2024 By analyzing temperature time series over more than 20 years, we have found a discrepancy between the 2 m temperature values reported by the ERA5 reanalysis and the automatic weather stations in the McMurdo Dry Valleys, Antarctica.

Sea ice cover in the Copernicus Arctic Regional Reanalysis

Sea ice cover in the Copernicus Arctic Regional Reanalysis Yurii Batrak, Bin Cheng, and Viivi Kallio-Myers The Cryosphere, 18, 1157–1183, https://doi.org/10.5194/tc-18-1157-2024, 2024 Atmospheric reanalyses provide consistent series of atmospheric and surface parameters in a convenient gridded form. In this paper, we study the quality of sea ice in a recently released regional reanalysis and assess its added value compared to a global reanalysis. We show that the regional reanalysis, having a more complex sea ice model, gives an improved representation of sea ice, although there are limitations indicating potential benefits in using more advanced approaches in the future.

India's water problems set to get worse as the world warms

Winter storms known as western disturbances that provide crucial snow and rainfall to northern India are arriving significantly later in the year.

Study explores impacts of Arctic warming on daily weather patterns in the U.S.

Arctic sea ice is shrinking as the world continues to warm, and a new study may provide a better understanding of how the loss of this ice may impact daily weather in the middle latitudes, like the United States.

On Russia's Arctic border, Nato's new members prep for war

New members Sweden and Finland joined the manoeuvres in northern Norway, aimed at deterring Russia.

Impact of boundary conditions on the modeled thermal regime of the Antarctic ice sheet

Impact of boundary conditions on the modeled thermal regime of the Antarctic ice sheet In-Woo Park, Emilia Kyung Jin, Mathieu Morlighem, and Kang-Kun Lee The Cryosphere, 18, 1139–1155, https://doi.org/10.5194/tc-18-1139-2024, 2024 This study conducted 3D thermodynamic ice sheet model experiments, and modeled temperatures were compared with 15 observed borehole temperature profiles. We found that using incompressibility of ice without sliding agrees well with observed temperature profiles in slow-flow regions, while incorporating sliding in fast-flow regions captures observed temperature profiles. Also, the choice of vertical velocity scheme has a greater impact on the shape of the modeled temperature profile.

The staggered retreat of grounded ice in the Ross Sea, Antarctica, since the Last Glacial Maximum (LGM)

The staggered retreat of grounded ice in the Ross Sea, Antarctica, since the Last Glacial Maximum (LGM) Matthew A. Danielson and Philip J. Bart The Cryosphere, 18, 1125–1138, https://doi.org/10.5194/tc-18-1125-2024, 2024 The post-Last Glacial Maximum (LGM) retreat of the West Antarctic Ice Sheet in the Ross Sea was more significant than for any other Antarctic sector. Here we combined the available dates of retreat with new mapping of sediment deposited by the ice sheet during overall retreat. Our work shows that the post-LGM retreat through the Ross Sea was not uniform. This uneven retreat can cause instability in the present-day Antarctic ice sheet configuration and lead to future runaway retreat.

New radar mission for Europe

Video: 00:09:27

The upcoming Copernicus Radar Observation System for Europe in L-band (ROSE-L) will provide continuous day-and-night all-weather monitoring of Earth’s land, oceans and ice, and offer frequent observations of Earth’s surface at a high spatial resolution.

ROSE-L will carry an active phased array synthetic aperture radar instrument. The radar antenna will be the largest deployable planar antenna ever built measuring an impressive 40 sq m.

ROSE-L will deliver many benefits including essential information on forests and land cover, leading to improved monitoring of the terrestrial carbon cycle and carbon accounting.

The mission will also greatly extend our ability to monitor minute surface displacements and helping detect geohazards. It will automatically map surface soil moisture conditions over land helping improve hydrology and weather forecasts, and support the operational monitoring of sea and land ice across the Arctic.

ROSE-L is one of six Copernicus Sentinel Expansion missions that ESA is developing on behalf of the EU. The missions will expand the current capabilities of the Copernicus Space Component – the world’s biggest supplier of Earth observation data.

This video features interviews with Malcolm Davidson, ROSE-L Mission Scientist, Nico Gebert, ROSE-L Payload Manager and Gianluigi Di Cosimo, ROSE-L Project Manager.

Access all Unpacking Sentinels videos.

After decades of Arctic sea ice getting faster and more hazardous for transport, models suggest a dramatic reversal is coming

Will ice floating in the Arctic Ocean move faster or slower over the coming decades? The answer to this question will tell us whether marine transportation can be expected to get more or less hazardous. It might also have important implications for the rate of ice cover loss, which is hugely consequential for Northern Indigenous communities, ecosystems, and the global climate system. While observational data suggest the trend has been towards faster sea ice speeds, climate models project that those speeds will slow down during the summer season. This contrast has led to some questions around the plausibility of the model projections.

We know the Arctic is warming -- What will changing river flows do to its environment?

Scientists recently combined satellite data, field observations and sophisticated numerical modeling to paint a picture of how 22.45 million square kilometers of the Arctic will change over the next 80 years. As expected, the overall region will be warmer and wetter, but the details -- up to 25% more runoff, 30% more subsurface runoff and a progressively drier southern Arctic, provides one of the clearest views yet of how the landscape will respond to climate change.

Arctic could become 'ice-free' within a decade

While summer sea ice loss in the Arctic is inevitable, it can be reversed if the planet cools down, researchers say.

Ice-free summers in Arctic possible within next decade, scientists say

Home of polar bears, seals and walruses could be mostly water for months as early as 2035 due to fossil fuel emissions

The Arctic could have summer days with practically no sea ice within the next decade due to emissions from burning fossil fuels, a study has found.

This would transform the unique habitat, home to polar bears, seals and walruses, from a “white Arctic” to a “blue Arctic” during the summer months, scientists said. The calculation used for “ice free” means less than 1m sq km, in which case the Arctic would be mostly water.

Regime shifts in Arctic terrestrial hydrology manifested from impacts of climate warming

Regime shifts in Arctic terrestrial hydrology manifested from impacts of climate warming Michael A. Rawlins and Ambarish V. Karmalkar The Cryosphere, 18, 1033–1052, https://doi.org/10.5194/tc-18-1033-2024, 2024 Flows of water, carbon, and materials by Arctic rivers are being altered by climate warming. We used simulations from a permafrost hydrology model to investigate future changes in quantities influencing river exports. By 2100 Arctic rivers will receive more runoff from the far north where abundant soil carbon can leach in. More water will enter them via subsurface pathways particularly in summer and autumn. An enhanced water cycle and permafrost thaw are changing river flows to coastal areas.

Why is summertime Arctic sea ice drift speed projected to decrease?

Why is summertime Arctic sea ice drift speed projected to decrease? Jamie L. Ward and Neil F. Tandon The Cryosphere, 18, 995–1012, https://doi.org/10.5194/tc-18-995-2024, 2024 Over the long term, the speed at which sea ice in the Arctic moves has been increasing during all seasons. However, nearly all climate models project that sea ice motion will decrease during summer. This study aims to understand the mechanisms responsible for these projected decreases in summertime sea ice motion. We find that models produce changes in winds and ocean surface tilt which cause the sea ice to slow down, and it is realistic to expect such changes to also occur in the real world.

The complex basal morphology and ice dynamics of the Nansen Ice Shelf, East Antarctica

The complex basal morphology and ice dynamics of the Nansen Ice Shelf, East Antarctica Christine F. Dow, Derek Mueller, Peter Wray, Drew Friedrichs, Alexander L. Forrest, Jasmin B. McInerney, Jamin Greenbaum, Donald D. Blankenship, Choon Ki Lee, and Won Sang Lee The Cryosphere, 18, 1105–1123, https://doi.org/10.5194/tc-18-1105-2024, 2024 Ice shelves are a key control on Antarctic contribution to sea level rise. We examine the Nansen Ice Shelf in East Antarctica using a combination of field-based and satellite data. We find the basal topography of the ice shelf is highly variable, only partially visible in satellite datasets. We also find that the thinnest region of the ice shelf is altered over time by ice flow rates and ocean melting. These processes can cause fractures to form that eventually result in large calving events.

Grain growth of ice doped with soluble impurities

Grain growth of ice doped with soluble impurities Qinyu Wang, Sheng Fan, and Chao Qi The Cryosphere, 18, 1053–1084, https://doi.org/10.5194/tc-18-1053-2024, 2024 We explored how the grain size of polycrystalline ice is affected by soluble impurities by conducting experiments on ice-containing salts. Results showed that above/below the eutectic point, impurities enhance/hinder grain growth, due to production of melts/precipitation of salt hydrates. Our findings offer insights into the dynamics of natural ice masses.

Velocity variations and hydrological drainage at Baltoro Glacier, Pakistan

Velocity variations and hydrological drainage at Baltoro Glacier, Pakistan Anna Wendleder, Jasmin Bramboeck, Jamie Izzard, Thilo Erbertseder, Pablo d'Angelo, Andreas Schmitt, Duncan J. Quincey, Christoph Mayer, and Matthias H. Braun The Cryosphere, 18, 1085–1103, https://doi.org/10.5194/tc-18-1085-2024, 2024 This study analyses the basal sliding and the hydrological drainage of Baltoro Glacier, Pakistan. The surface velocity was characterized by a spring speed-up, summer peak, and autumn speed-up. Snow melt has the largest impact on the spring speed-up, summer velocity peak, and the transition from inefficient to efficient drainage. Drainage from supraglacial lakes contributed to the fall speed-up. Increased summer temperatures will intensify the magnitude of meltwater and thus surface velocities.

Less ice in the Arctic Ocean has complex effects on marine ecosystems and ocean productivity

Most of the sunlight reaching the Arctic Ocean is reflected to space by sea ice, effectively shielding ocean ecosystems from sunlight. As the Arctic sea ice continues its downward trend, larger areas of the ocean become exposed to sunlight for longer periods, potentially allowing more primary production on the seafloor. However, according to a new study, this anticipated increase in primary production does not seem to be occurring uniformly across the Arctic Ocean.

Antarctica's coasts are becoming less icy

Scientists found unexpected evidence the area of polynyas around Antarctica is increasing dramatically, and it follows an intriguing cycle, growing and shrinking roughly every 16 years.

Leaping toward spring

During February, Arctic sea ice extent increased along the lower 10 percent interdecile value, with the average monthly extent tied for fifteenth lowest in the satellite record. Temperatures were above average over the central Arctic, but still well below freezing. Antarctic … Continue reading →

Smoothed particle hydrodynamics implementation of the standard viscous–plastic sea-ice model and validation in simple idealized experiments

Smoothed particle hydrodynamics implementation of the standard viscous–plastic sea-ice model and validation in simple idealized experiments Oreste Marquis, Bruno Tremblay, Jean-François Lemieux, and Mohammed Islam The Cryosphere, 18, 1013–1032, https://doi.org/10.5194/tc-18-1013-2024, 2024 We developed a standard viscous–plastic sea-ice model based on the numerical framework called smoothed particle hydrodynamics. The model conforms to the theory within an error of 1 % in an idealized ridging experiment, and it is able to simulate stable ice arches. However, the method creates a dispersive plastic wave speed. The framework is efficient to simulate fractures and can take full advantage of parallelization, making it a good candidate to investigate sea-ice material properties.

The effect of landfast sea ice buttressing on ice dynamic speedup in the Larsen B embayment, Antarctica

The effect of landfast sea ice buttressing on ice dynamic speedup in the Larsen B embayment, Antarctica Trystan Surawy-Stepney, Anna E. Hogg, Stephen L. Cornford, Benjamin J. Wallis, Benjamin J. Davison, Heather L. Selley, Ross A. W. Slater, Elise K. Lie, Livia Jakob, Andrew Ridout, Noel Gourmelen, Bryony I. D. Freer, Sally F. Wilson, and Andrew Shepherd The Cryosphere, 18, 977–993, https://doi.org/10.5194/tc-18-977-2024, 2024 Here, we use satellite observations and an ice flow model to quantify the impact of sea ice buttressing on ice streams on the Antarctic Peninsula. The evacuation of 11-year-old landfast sea ice in the Larsen B embayment on the East Antarctic Peninsula in January 2022 was closely followed by major changes in the calving behaviour and acceleration (30 %) of the ocean-terminating glaciers. Our results show that sea ice buttressing had a negligible direct role in the observed dynamic changes.

Watch: Ploughing through California and Nevada snow

A massive blizzard sweeps across parts of California and Nevada in the western United States.

Massive blizzard hits western United States

The snowstorm hit California's Sierra Nevada mountains especially hard, with up to 10ft of snow expected.

2020 extreme weather event that brought fires and snow to western US

The same weather system that led to the spread of the devastating Labor Day wildfires in 2020 brought record-breaking cold and early-season snowfall to parts of the Rocky Mountains. Now, new research is shedding light on the meteorology behind what happened and the impacts of such an extreme weather event.

Loss of Sea Ice in Antarctica Is "Nothing Short of Shocking"

The extent of Antarctic sea ice has reached its yearly minimum, tying for second as lowest on record.

No snow, no tourists - death of a Swiss ski resort

Rüschegg Eywald boasts the fourth longest ski lift in Switzerland. This year, it didn't open once.

California mountain regions brace for huge snowstorm

Resorts and roads are closing ahead of an expected 10 feet of snow in the Sierra Nevada mountains.

Scientists have new details on an Antarctic glacier crucial to future sea level rise

NPR's Ari Shapiro talks with glaciologist Ted Scambos about the conclusion of a multi-year study of Antarctica's Thwaites Glacier, the "plug" holding back a formidable amount of ice.

Researchers use GPS-tracked icebergs in novel study to improve climate models

Research unearthed new information to help scientists better understand circulation patterns of ocean water around glaciers. In the summers of 2014 and 2019, a group of pioneers in glacial research attached GPS devices to 13 icebergs and tracked hourly changes in their positions as they passed through Greenland's Ilulissat Icefjord toward the ocean. Study results showed circulation in the primary fjord is greatly affected by freshwater flow from connecting tributary fjords, which is critically important to consider in circulation models.

Glacier shrinkage is causing a 'green transition'

Glacier-fed streams are undergoing a process of profound change, according to scientists. This conclusion is based on the expeditions to the world's major mountain ranges by members of the Vanishing Glaciers project.

Night-shining cloud mission ends; yields high science results for NASA

After 16 years studying Earth's highest clouds for the benefit of humanity—polar mesospheric clouds—from its orbit some 350 miles above the ground, NASA's Aeronomy of Ice in the Mesosphere, or AIM, mission has come to an end.

'Nobody is scared' - crowds defiant at Navalny's funeral

Risking arrest, large numbers paid tribute to the Putin critic, who died in an Arctic prison.

Earth from Space: Dawson-Lambton Glacier home to penguins

Image: This Copernicus Sentinel-2 image features the ice tongue of the Dawson-Lambton Glacier in Antarctica.

Effects of Arctic sea-ice concentration on turbulent surface fluxes in four atmospheric reanalyses

Effects of Arctic sea-ice concentration on turbulent surface fluxes in four atmospheric reanalyses Tereza Uhlíková, Timo Vihma, Alexey Yu Karpechko, and Petteri Uotila The Cryosphere, 18, 957–976, https://doi.org/10.5194/tc-18-957-2024, 2024 A prerequisite for understanding the local, regional, and hemispherical impacts of Arctic sea-ice decline on the atmosphere is to quantify the effects of sea-ice concentration (SIC) on the sensible and latent heat fluxes in the Arctic. We analyse these effects utilising four data sets called atmospheric reanalyses, and we evaluate uncertainties in these effects arising from inter-reanalysis differences in SIC and in the sensitivity of the latent and sensible heat fluxes to SIC.

Global emergent responses of stream microbial metabolism to glacier shrinkage

Nature Geoscience, Published online: 01 March 2024; doi:10.1038/s41561-024-01393-6

Surprising methane discovery in Yukon glaciers: 'Much more widespread than we thought'

Global melting is prying the lid off methane stocks, the extent of which we do not know. A researcher has now discovered high concentrations of the powerful greenhouse gas in meltwater from three Canadian mountain glaciers, where it was not thought to exist -- adding new unknowns to the understanding of methane emissions from Earth's glaciated regions.

Melt pond fractions on Arctic summer sea ice retrieved from Sentinel-3 satellite data with a constrained physical forward model

Melt pond fractions on Arctic summer sea ice retrieved from Sentinel-3 satellite data with a constrained physical forward model Hannah Niehaus, Larysa Istomina, Marcel Nicolaus, Ran Tao, Aleksey Malinka, Eleonora Zege, and Gunnar Spreen The Cryosphere, 18, 933–956, https://doi.org/10.5194/tc-18-933-2024, 2024 Melt ponds are puddles of meltwater which form on Arctic sea ice in the summer period. They are darker than the ice cover and lead to increased absorption of solar energy. Global climate models need information about the Earth's energy budget. Thus satellite observations are used to monitor the surface fractions of melt ponds, ocean, and sea ice in the entire Arctic. We present a new physically based algorithm that can separate these three surface types with uncertainty below 10 %.

Why Do We Need A Leap Day? So It Doesn’t Snow In The ‘Summer’

If Earth let all its extra quarter days add up, we’d quickly be celebrating the 4th of July when it’s snowing.

80 mph speed record for glacier fracture helps reveal the physics of ice sheet collapse

New research documents the fastest-known large-scale breakage along an Antarctic ice shelf. A 6.5-mile crack formed in 2012 over 5-and-a-half minutes, showing that ice shelves can effectively shatter -- though the speed is limited by seawater rushing in. The results help inform large-scale ice sheet models and projections of future sea level rise.

Antarctic sea ice extent hits a third low in a row

On February 20, Antarctic sea ice likely reached its minimum extent of 1.99 million square kilometers (768,000 square miles), tying for second lowest extent in the 1979 to 2024 satellite record. This is the third consecutive year that Antarctic sea … Continue reading →

Chemistry in the ground affects how many offspring wild animals have

Chemistry in the ground affect how many kids wild animals have Areas with more copper and selenium in the ground lead to higher reproductive success in wild musk oxen in Greenland.

Are Leopard Seals as Dangerous as You Think?

Leopard seals are apex predators in the Antarctic region but they generally do not pose a significant threat to humans. Learn more about their behavior and the potential risks regarding human interaction.

Local forcing mechanisms challenge parameterizations of ocean thermal forcing for Greenland tidewater glaciers

Local forcing mechanisms challenge parameterizations of ocean thermal forcing for Greenland tidewater glaciers Alexander O. Hager, David A. Sutherland, and Donald A. Slater The Cryosphere, 18, 911–932, https://doi.org/10.5194/tc-18-911-2024, 2024 Warming ocean temperatures cause considerable ice loss from the Greenland Ice Sheet; however climate models are unable to resolve the complex ocean processes within fjords that influence near-glacier ocean temperatures. Here, we use a computer model to test the accuracy of assumptions that allow climate and ice sheet models to project near-glacier ocean temperatures, and thus glacier melt, into the future. We then develop new methods that improve accuracy by accounting for local ocean processes.

Researchers leverage machine learning to improve space weather predictions

There are three levels of severity for space storms: geomagnetic storms, solar radiation storms and radio blackouts. These storms produce different effects on Earth, including satellite, GPS, communications and electrical grid issues, as well as health dangers for astronauts and people on high-altitude flights. Geomagnetic storms also produce the beautiful auroras that are commonly observed in polar regions.

Extent, duration and timing of the sea ice cover in Hornsund, Svalbard, from 2014–2023

Extent, duration and timing of the sea ice cover in Hornsund, Svalbard, from 2014–2023 Zuzanna M. Swirad, A. Malin Johansson, and Eirik Malnes The Cryosphere, 18, 895–910, https://doi.org/10.5194/tc-18-895-2024, 2024 We used satellite images to create sea ice maps of Hornsund fjord, Svalbard, for nine seasons and calculated the percentage of the fjord that was covered by ice. On average, sea ice was present in Hornsund for 158 d per year, but it varied from year to year. April was the "iciest'" month and 2019/2020, 2021/22 and 2014/15 were the "iciest'" seasons. Our data can be used to understand sea ice conditions compared with other fjords of Svalbard and in studies of wave modelling and coastal erosion.

Brief communication: Recent estimates of glacier mass loss for western North America from laser altimetry

Brief communication: Recent estimates of glacier mass loss for western North America from laser altimetry Brian Menounos, Alex Gardner, Caitlyn Forentine, and Andrew Fountain The Cryosphere, 18, 889–894, https://doi.org/10.5194/tc-18-889-2024, 2024 Glaciers in western North American outside of Alaska are often overlooked in global studies because their potential to contribute to changes in sea level is small. Nonetheless, these glaciers represent important sources of freshwater, especially during times of drought. We show that these glaciers lost mass at a rate of about 12 Gt yr-1 for about the period 2013–2021;  the rate of mass loss over the period 2018–2022 was similar. 

Significant glacial retreat in West Antarctica began in 1940s

Among the vast expanse of Antarctica lies the Thwaites Glacier, the world's widest glacier measuring about 80 miles on the western edge of the continent. Despite its size, the massive landform is losing about 50 billion tons of ice more than it is receiving in snowfall, which places it in a precarious position in respect to its stability. Accelerating ice loss has been observed since the 1970s, but it is unclear when this significant melting initiated -- until now. A new study suggests that the significant glacial retreat of two glaciers on the west coast of Antarctica began in the 1940's, likely spurred by climate change.

'Ice bumps' reveal history of Antarctic melting

Satellites reveal a 50-year record of climate change by tracing the lumpiness in ice surfaces.

Russia’s Arctic Council threat requires lessons from cold war science diplomacy

Nature, Published online: 27 February 2024; doi:10.1038/d41586-024-00557-z

Steward Observatory balloon mission breaks NASA record 22 miles above Antarctica

Fifty-eight days ago, on a nearly windless morning on the Ross Ice Shelf, a stadium-size balloon took flight above Antarctica, carrying with it far infrared technology from the University of Arizona's Steward Observatory in search of clues about the stellar life cycle in our galaxy and beyond.

Astronomers spot white dwarf star with metallic ‘scar’

Patch on Earth-sized remnant of star covers larger fraction of pole than equivalent of Antarctica on Earth

Astronomers have spotted a star with a dark metallic “scar” on its surface, thought to be the imprint of a doomed planetary fragment that came too close to its host.

The white dwarf star, called WD 0816-310, is a dense, Earth-sized remnant of a star about 63 light years away that would have been similar to our sun in its lifetime. Observations revealed a concentrated patch of metals on its surface, which appear to be the remnants of an ingested chunk of planet or an asteroid.

Scientists confirm first cases of bird flu on mainland Antarctica

Fears for penguin colonies after the discovery of the highly contagious H5N1 virus in two dead skuas

Bird flu has reached mainland of Antarctica for the first time, officials have confirmed.

The H5N1 virus was found on Friday in two dead scavenging birds called skuas near Primavera Base, the Argentinian scientific research station on the Antarctic peninsula.

Forward modelling of synthetic-aperture radar (SAR) backscatter during lake ice melt conditions using the Snow Microwave Radiative Transfer (SMRT) model

Forward modelling of synthetic-aperture radar (SAR) backscatter during lake ice melt conditions using the Snow Microwave Radiative Transfer (SMRT) model Justin Murfitt, Claude Duguay, Ghislain Picard, and Juha Lemmetyinen The Cryosphere, 18, 869–888, https://doi.org/10.5194/tc-18-869-2024, 2024 This research focuses on the interaction between microwave signals and lake ice under wet conditions. Field data collected for Lake Oulujärvi in Finland were used to model backscatter under different conditions. The results of the modelling likely indicate that a combination of increased water content and roughness of different interfaces caused backscatter to increase. These results could help to identify areas where lake ice is unsafe for winter transportation.

US spacecraft on the moon ‘caught a foot’ and tipped on to side, says Nasa

Intuitive Machines CEO says Odysseus tipped over and ended up on its side as it landed on to south polar region

Odysseus, the first US-built spacecraft to touchdown on the moon in more than half a century, is tipped over on its side, according to an update from Nasa and Intuitive Machines, the company that built and operated the lander.

The robotic lander descended on to the south polar region of the moon on Thursday at 6.23pm ET. But several minutes passed before flight controllers were able to pick up a signal from the lander’s communication systems.

A novel framework to investigate wind-driven snow redistribution over an Alpine glacier: combination of high-resolution terrestrial laser scans and large-eddy simulations

A novel framework to investigate wind-driven snow redistribution over an Alpine glacier: combination of high-resolution terrestrial laser scans and large-eddy simulations Annelies Voordendag, Brigitta Goger, Rainer Prinz, Tobias Sauter, Thomas Mölg, Manuel Saigger, and Georg Kaser The Cryosphere, 18, 849–868, https://doi.org/10.5194/tc-18-849-2024, 2024 Wind-driven snow redistribution affects glacier mass balance. A case study of Hintereisferner glacier in Austria used high-resolution observations and simulations to model snow redistribution. Simulations matched observations, showing the potential of the model for studying snow redistribution on other mountain glaciers.

Barriers against Antarctic ice melt disappearing at the double

Undersea anchors of ice that help prevent Antarctica's land ice from slipping into the ocean are shrinking at more than twice the rate compared with 50 years ago, research shows. More than a third of these frozen moorings, known as pinning points, have decreased in size since the turn of the century, experts say. Further deterioration of pinning points, which hold in place the floating ice sheets that fortify Antarctica's land ice, would accelerate the continent's contribution to rising sea levels, scientists warn.

ESA satellite returns to Earth – ERS-2 reentry

Video: 00:03:29

Mission complete. ESA’s second European Remote Sensing (ERS-2) satellite has reentered Earth’s atmosphere over the North Pacific Ocean. The satellite returned at 18:17 CET (17:17 UTC) between Alaska and Hawaii.

ERS-2 was launched almost 30 years ago, on 21 April 1995. Together with ERS-1, it provided invaluable long-term data on Earth’s land surfaces, ocean temperatures, ozone layer and polar ice extent that revolutionised our understanding of the Earth system.

ERS-2’s reentry was ‘natural’. ESA used the last of its fuel, emptied its batteries and lowered the satellite from its altitude of 785 km to 573 km. This reduced the risk of collision with other satellites and space debris. As a result, it was not possible to control ERS-2 at any point during its reentry and the only force driving its descent was unpredictable atmospheric drag.

As well as leaving a remarkable legacy of data that still continue to advance science, this outstanding mission set the stage for many of today’s satellites and ESA’s position at the forefront of Earth observation.

The ERS-2 reentry is part of ESA's wider efforts to ensure the long-term sustainability of space activities. These include ESA's Clean Space initiative which promotes the development of new technologies for more sustainable space missions in collaboration with the wider European space community, as well as the Zero Debris Approach, which will even further reduce the debris left in both Earth and lunar orbits by future missions.

New mission to track changes in the cryosphere

Video: 00:15:00

Tracking ice lost from the world’s glaciers, ice sheets and frozen land shows that Earth is losing ice at an accelerating rate. Monitoring the cryosphere is crucial for assessing, predicting and adapting to climate change.

The Copernicus Polar Ice and Snow Topography Altimeter (CRISTAL) mission will provide a full picture of the changes taking place in some of the most inhospitable regions of the world. It will carry – for the first time – a dual-frequency radar altimeter, and microwave radiometer, that will measure and monitor sea-ice thickness, overlying snow depth and ice-sheet elevations.

These data will support maritime operations in the polar oceans and contribute to a better understanding of climate processes. CRISTAL will also support applications related to coastal and inland waters, as well as providing observations of ocean topography.

CRISTAL is one of six Copernicus Sentinel Expansion missions that ESA is developing on behalf of the EU. The missions will expand the current capabilities of the Copernicus Space Component – the world’s biggest supplier of Earth observation data.

This video features interviews with Kristof Gantois, CRISTAL Project Manager and Paolo Cipollini, CRISTAL Mission Scientist.

It’s a wrap, a swim and an ice sculpture

With ESA’s Biomass in the latter stages of development, two intrepid scientists have been braving the cold in the icy reaches of Antarctica for two months to take measurements from the air and from the ground to help prepare for this new satellite mission. With their expedition now complete, here’s the report [...]

Moment giant Antarctica drone takes off

Scientists want to use the robot plane to reach inaccessible areas to understand climate change.

Ice plate deformation and cracking revealed by an in situ-distributed acoustic sensing array

Ice plate deformation and cracking revealed by an in situ-distributed acoustic sensing array Jun Xie, Xiangfang Zeng, Chao Liang, Sidao Ni, Risheng Chu, Feng Bao, Rongbing Lin, Benxin Chi, and Hao Lv The Cryosphere, 18, 837–847, https://doi.org/10.5194/tc-18-837-2024, 2024 Seismology can help study the mechanism of disintegration of floating ice plates. We conduct a seismic experiment on a frozen lake using a distributed acoustic sensing array. Icequakes and low-frequency events are detected with an artificial intelligence method. Our study demonstrates the merit of distributed acoustic sensing array in illuminating the internal failure process and properties of the ice shelf, which eventually contributes to the understanding and prediction of ice shelf collapse.

Progressive unanchoring of Antarctic ice shelves since 1973

Nature, Published online: 21 February 2024; doi:10.1038/s41586-024-07049-0

Decline in microbial genetic richness in the western Arctic Ocean

Researchers analyzed archival samples of bacteria and archaea populations taken from the Beaufort Sea, bordering northwest Canada and Alaska. The samples were collected between 2004 and 2012, a period that included two years -- 2007 and 2012 -- in which the sea ice coverage was historically low. The researchers looked at samples taken from three levels of water: the summer mixed layer, the upper Arctic water below it and the Pacific-origin water at the deepest level. The study examined the microbes' genetic composition using bioinformatics and statistical analysis across the nine-year time span. Using this data, the researchers were able to see how changing environmental conditions were influencing the organisms' structure and function.

Let me see my son's body - Navalny's mother to Putin

Lyudmila Navalnaya makes a plea to Putin to release Alexei's body after he died in an Arctic prison.

Partial melting in polycrystalline ice: pathways identified in 3D neutron tomographic images

Partial melting in polycrystalline ice: pathways identified in 3D neutron tomographic images Christopher J. L. Wilson, Mark Peternell, Filomena Salvemini, Vladimir Luzin, Frieder Enzmann, Olga Moravcova, and Nicholas J. R. Hunter The Cryosphere, 18, 819–836, https://doi.org/10.5194/tc-18-819-2024, 2024 As the temperature increases within a deforming ice aggregate, composed of deuterium (D2O) ice and water (H2O) ice, a set of meltwater segregations are produced. These are composed of H2O and HDO and are located in conjugate shear bands and in compaction bands which accommodate the deformation and weaken the ice aggregate. This has major implications for the passage of meltwater in ice sheets and the formation of the layering recognized in glaciers.

Meteoric water and glacial melt in the southeastern Amundsen Sea: a time series from 1994 to 2020

Meteoric water and glacial melt in the southeastern Amundsen Sea: a time series from 1994 to 2020 Andrew N. Hennig, David A. Mucciarone, Stanley S. Jacobs, Richard A. Mortlock, and Robert B. Dunbar The Cryosphere, 18, 791–818, https://doi.org/10.5194/tc-18-791-2024, 2024 A total of 937 seawater paired oxygen isotope (δ18O)–salinity samples collected during seven cruises on the SE Amundsen Sea between 1994 and 2020 reveal a deep freshwater source with δ18O − 29.4±1.0‰, consistent with the signature of local ice shelf melt. Local mean meteoric water content – comprised primarily of glacial meltwater – increased between 1994 and 2020 but exhibited greater interannual variability than increasing trend. 

Globally consistent estimates of high-resolution Antarctic ice mass balance and spatially resolved glacial isostatic adjustment

Globally consistent estimates of high-resolution Antarctic ice mass balance and spatially resolved glacial isostatic adjustment Matthias O. Willen, Martin Horwath, Eric Buchta, Mirko Scheinert, Veit Helm, Bernd Uebbing, and Jürgen Kusche The Cryosphere, 18, 775–790, https://doi.org/10.5194/tc-18-775-2024, 2024 Shrinkage of the Antarctic ice sheet (AIS) leads to sea level rise. Satellite gravimetry measures AIS mass changes. We apply a new method that overcomes two limitations: low spatial resolution and large uncertainties due to the Earth's interior mass changes. To do so, we additionally include data from satellite altimetry and climate and firn modelling, which are evaluated in a globally consistent way with thoroughly characterized errors. The results are in better agreement with independent data.

Bayesian physical–statistical retrieval of snow water equivalent and snow depth from X- and Ku-band synthetic aperture radar – demonstration using airborne SnowSAr in SnowEx'17

Bayesian physical–statistical retrieval of snow water equivalent and snow depth from X- and Ku-band synthetic aperture radar – demonstration using airborne SnowSAr in SnowEx'17 Siddharth Singh, Michael Durand, Edward Kim, and Ana P. Barros The Cryosphere, 18, 747–773, https://doi.org/10.5194/tc-18-747-2024, 2024 Seasonal snowfall accumulation plays a critical role in climate. The water stored in it is measured by the snow water equivalent (SWE), the amount of water released after completely melting. We demonstrate a Bayesian physical–statistical framework to estimate SWE from airborne X- and Ku-band synthetic aperture radar backscatter measurements constrained by physical snow hydrology and radar models. We explored spatial resolutions and vertical structures that agree well with ground observations.

Viruses that can help 'dial up' carbon capture in the sea

Armed with a catalog of hundreds of thousands of DNA and RNA virus species in the world's oceans, scientists are now zeroing in on the viruses most likely to combat climate change by helping trap carbon dioxide in seawater or, using similar techniques, different viruses that may prevent methane's escape from thawing Arctic soil.

Landslide kills 25 after heavy snow in Afghanistan

Rescuers with shovels and axes are trying to find survivors in the country's eastern province.

A low-cost and open-source approach for supraglacial debris thickness mapping using UAV-based infrared thermography

A low-cost and open-source approach for supraglacial debris thickness mapping using UAV-based infrared thermography Jérôme Messmer and Alexander Raphael Groos The Cryosphere, 18, 719–746, https://doi.org/10.5194/tc-18-719-2024, 2024 The lower part of mountain glaciers is often covered with debris. Knowing the thickness of the debris is important as it influences the melting and future evolution of the affected glaciers. We have developed an open-source approach to map variations in debris thickness on glaciers using a low-cost drone equipped with a thermal infrared camera. The resulting high-resolution maps of debris surface temperature and thickness enable more accurate monitoring and modelling of debris-covered glaciers.

Alexei Navalny's team seeks answers as mother barred from mortuary

The Russian opposition leader's mother was trying to enter a mortuary near the remote Arctic prison where he died, a spokeswoman says.

Giant Antarctic sea spiders reproductive mystery solved

Instead of carrying the babies until they hatched, as in most species of sea spiders, one parent (likely the father) spent two days attaching the eggs to the rocky bottom where they developed for several months before hatching as tiny larvae.

The week in TV: Alice & Jack; The Space Shuttle That Fell to Earth; The New Look; Bring the Drama – review

Andrea Riseborough and Domhnall Gleeson convince as a perma-turbulent couple; a devastating docuseries pays homage to the doomed Columbia space shuttle crew. Plus, ill-fitting wartime drama with Coco Chanel and Christian Dior and a sweet, old-school reality show

Alice & Jack (Channel 4) | channel4.comThe Space Shuttle That Fell to Earth (BBC Two) | iPlayerThe New Look (Apple TV+)Bring the Drama (BBC Two) | iPlayer

What’s in the ether with sputtering, on-off romances at the moment? We’ve just had the Netflix adaptation of One Day (college couple circle each other for 20 years). Now, there’s Victor Levin’s Alice & Jack, a six-part Channel 4 drama devoted to decades-spanning romantic dysfunction. Part-directed by Juho Kuosmanen (Compartment No 6) and Hong Khaou, if it’s meant as a TV valentine (the opener aired last Tuesday, 14 February), it’s an emotionally visceral one, with cerebral entrails dangling out.

Carnival, kisses and snow: Photos of the week

A selection of striking images from around the world, taken over the past seven days.

Navalny’s life in 'Polar Wolf' remote penal colony

Only those accused of the very worst crimes are sent to IK-3, the strictest penal colony imaginable.

Beyond peak season: Bacteria in the Arctic seabed are active all year round

Researchers studied the composition and function of bacteria in the seabed off Svalbard, during alternating periods of polar night and midnight sun. To do this, they specially developed a sampling device, the Ellrott grab. In contrast with bacterial communities in the overlying water, the sediment bacteria hardly change with the seasons. This is probably due to the fact that in the seabed some hard-to-digest foods are available all year round.

Aurora borealis dynamics suggest the polar vortex is breaking up again

The Space Climate Research Group at the University of Oulu, Finland has been studying the effects of energetic particle precipitation from space, more commonly known as the aurora borealis or Northern Lights, on winter weather variations for quite some time. The aurora borealis is not only a beautiful light phenomenon, but also involves chemical changes that lead to ozone depletion high in the polar stratosphere in winter.

Alexei Navalny jokes in January video from penal colony

The Russian opposition leader was moved to a prison in the Arctic Circle in December.

What does a warming Arctic mean for the future?

Video: 00:12:27

The Arctic is experiencing disproportionately higher temperature increases compared to the rest of the planet, triggering a series of cascading effects. This rapid warming has profound implications for global climate patterns, human populations and wildlife.

The Copernicus Imaging Microwave Radiometer mission (CIMR) will provide measurements to decision makers with evidence of change and impact in the polar regions – with a focus on the Arctic.

The mission has the largest radiometer developed by ESA and will provide high-resolution measurements related to sea ice, the ocean, snow and ice-sheet surfaces. This will be crucial in understanding the evolution of the climate in the polar region.

CIMR is one of six Copernicus Sentinel Expansion missions that ESA is developing on behalf of the EU. The missions will expand the current capabilities of the Copernicus Space Component – the world’s biggest supplier of Earth observation data.

This video features interviews with Craig Donlon, CIMR Mission Scientist, Rolv Midthassel, CIMR Payload Manager, Claudio Galeazzi, CIMR Project Manager, Mariel Triggianese, CIMR Satellite Engineering and AIV Manager, and Marcello Sallusti, CIMR System Performance and Operations Manager.

In the meantime Craig has changed his role but will retain his position as Mission Scientist.

Big cats can tell apart known and unknown human voices, study finds

Tigers, cheetahs and snow leopards, like domesticated cats, respond differently to familiar and unfamiliar voices

From tigers to cheetahs, big cats may seem majestically aloof but researchers have found they can tell apart familiar and unfamiliar human voices, suggesting that even animals that shun group living are far from socially inept.

While cats are often portrayed as somewhat standoffish, researchers have previously found that domesticated felines can tell apart the voice of their owner from that of other humans.

The role of jellies as a food source in the Arctic winter

The Arctic is changing rapidly due to climate change. It is not only affected by increasing surface temperatures, but also by warm water from the Atlantic, which is flowing in more and more -- changing the structures and functions of the ecosystem as it also leads to species from warmer regions, such as sea jellies (also known as jellyfish) arriving in the Arctic. Using DNA metabarcoding, researchers have now been able to demonstrate that these jellyfish serve as food for amphipods on Svalbard during the polar night and thus play a greater role in Arctic food webs than previously assumed.

Brief communication: An ice-debris avalanche in the Nupchu Valley, Kanchenjunga Conservation Area, eastern Nepal

Brief communication: An ice-debris avalanche in the Nupchu Valley, Kanchenjunga Conservation Area, eastern Nepal Alton C. Byers, Marcelo Somos-Valenzuela, Dan H. Shugar, Daniel McGrath, Mohan B. Chand, and Ram Avtar The Cryosphere, 18, 711–717, https://doi.org/10.5194/tc-18-711-2024, 2024 In spite of enhanced technologies, many large cryospheric events remain unreported because of their remoteness, inaccessibility, or poor communications. In this Brief communication, we report on a large ice-debris avalanche that occurred sometime between 16 and 21 August 2022 in the Kanchenjunga Conservation Area (KCA), eastern Nepal. 

Fire and Ice: Dramatic New Volcanic Eruption in Iceland, as Seen From Space

Satellite imagery of the eruption shows fiery hot lava against a landscape covered in snow.

Boreal–Arctic wetland methane emissions modulated by warming and vegetation activity

Nature Climate Change, Published online: 14 February 2024; doi:10.1038/s41558-024-01933-3

Wetland emissions on the rise

Nature Climate Change, Published online: 14 February 2024; doi:10.1038/s41558-024-01938-y

Into the belly of the rover: VIPER's final science instrument installed

A team of engineers is preparing to integrate TRIDENT—short for The Regolith Ice Drill for Exploring New Terrain—into the belly of NASA's first robotic moon rover, VIPER (Volatiles Investigating Polar Exploration Rover).

New Yorkers brave heavy snow to vote in special election to replace ex-Rep. George Santos

Democratic candidate Tom Suozzi is facing off against Republican Mazi Pilip in a special election to fill the seat vacated by expelled ex-Rep. George Santos.

Frequent marine heatwaves in the Arctic Ocean will be the norm

Marine heatwaves will become a regular occurrence in the Arctic in the near future and are a product of higher anthropogenic greenhouse-gas emissions -- as shown in a new study.

Greenland's ice sheet is melting -- and being replaced by vegetation

An estimated 11,000 sq miles or 28,707 sq kilometers of Greenland's ice sheet and glaciers have melted over the last three decades, according to a major analysis of historic satellite records.

Polar bears unlikely to adapt to longer summers

More time stranded on land means greater risk of starvation for polar bears, a new study indicates. During three summer weeks, 20 polar bears closely observed by scientists tried different strategies to maintain energy reserves, including resting, scavenging and foraging. Yet nearly all of them lost weight rapidly: on average around 1 kilogram, or 2.2 pounds, per day. Some have speculated that polar bears might adapt to the longer ice-free seasons due to climate warming by acting like their grizzly bear relatives and either rest or eat terrestrial food. The polar bears in this study tried versions of both strategies -- with little success.

Is That Polar Bear Getting Enough to Eat? Try a Collar With a Camera.

Scientists collected video from 20 bears during ice-free months to understand whether the animals can survive longer periods on land in a warming world.

Polar bears face starvation threat as ice melts

Melting ice is forcing this iconic Arctic species to spend more time on land, where they struggle for food.

World famous New York skyline obscured by snow

Videos from the city and parts of the state show what areas look like after being hit by the snow storm.

Brief communication: Rapid acceleration of the Brunt Ice Shelf after calving of iceberg A-81

Brief communication: Rapid acceleration of the Brunt Ice Shelf after calving of iceberg A-81 Oliver J. Marsh, Adrian J. Luckman, and Dominic A. Hodgson The Cryosphere, 18, 705–710, https://doi.org/10.5194/tc-18-705-2024, 2024 The Brunt Ice Shelf has accelerated rapidly after calving an iceberg in January 2023. A decade of GPS data show that the rate of acceleration in August 2023 was 30 times higher than before calving, and velocity has doubled in 6 months. Satellite velocity maps show the extent of the change. The acceleration is due to loss of contact between the ice shelf and a pinning point known as the McDonald Ice Rumples. The observations highlight how iceberg calving can directly impact ice shelves.

Evaporative controls on Antarctic precipitation: an ECHAM6 model study using innovative water tracer diagnostics

Evaporative controls on Antarctic precipitation: an ECHAM6 model study using innovative water tracer diagnostics Qinggang Gao, Louise C. Sime, Alison J. McLaren, Thomas J. Bracegirdle, Emilie Capron, Rachael H. Rhodes, Hans Christian Steen-Larsen, Xiaoxu Shi, and Martin Werner The Cryosphere, 18, 683–703, https://doi.org/10.5194/tc-18-683-2024, 2024 Antarctic precipitation is a crucial component of the climate system. Its spatio-temporal variability impacts sea level changes and the interpretation of water isotope measurements in ice cores. To better understand its climatic drivers, we developed water tracers in an atmospheric model to identify moisture source conditions from which precipitation originates. We find that mid-latitude surface winds exert an important control on moisture availability for Antarctic precipitation.

Disentangling the drivers of future Antarctic ice loss with a historically calibrated ice-sheet model

Disentangling the drivers of future Antarctic ice loss with a historically calibrated ice-sheet model Violaine Coulon, Ann Kristin Klose, Christoph Kittel, Tamsin Edwards, Fiona Turner, Ricarda Winkelmann, and Frank Pattyn The Cryosphere, 18, 653–681, https://doi.org/10.5194/tc-18-653-2024, 2024 We present new projections of the evolution of the Antarctic ice sheet until the end of the millennium, calibrated with observations. We show that the ocean will be the main trigger of future ice loss. As temperatures continue to rise, the atmosphere's role may shift from mitigating to amplifying Antarctic mass loss already by the end of the century. For high-emission scenarios, this may lead to substantial sea-level rise. Adopting sustainable practices would however reduce the rate of ice loss.

Coupling MAR (Modèle Atmosphérique Régional) with PISM (Parallel Ice Sheet Model) mitigates the positive melt–elevation feedback

Coupling MAR (Modèle Atmosphérique Régional) with PISM (Parallel Ice Sheet Model) mitigates the positive melt–elevation feedback Alison Delhasse, Johanna Beckmann, Christoph Kittel, and Xavier Fettweis The Cryosphere, 18, 633–651, https://doi.org/10.5194/tc-18-633-2024, 2024 Aiming to study the long-term influence of an extremely warm climate in the Greenland Ice Sheet contribution to sea level rise, a new regional atmosphere–ice sheet model setup was established. The coupling, explicitly considering the melt–elevation feedback, is compared to an offline method to consider this feedback. We highlight mitigation of the feedback due to local changes in atmospheric circulation with changes in surface topography, making the offline correction invalid on the margins.

Snow water equivalent retrieval over Idaho – Part 2: Using L-band UAVSAR repeat-pass interferometry

Snow water equivalent retrieval over Idaho – Part 2: Using L-band UAVSAR repeat-pass interferometry Zachary Hoppinen, Shadi Oveisgharan, Hans-Peter Marshall, Ross Mower, Kelly Elder, and Carrie Vuyovich The Cryosphere, 18, 575–592, https://doi.org/10.5194/tc-18-575-2024, 2024 We used changes in radar echo travel time from multiple airborne flights to estimate changes in snow depths across Idaho for two winters. We compared our radar-derived retrievals to snow pits, weather stations, and a 100 m resolution numerical snow model. We had a strong Pearson correlation and root mean squared error of 10 cm relative to in situ measurements. Our retrievals also correlated well with our model, especially in regions of dry snow and low tree coverage.

Recent warming trends of the Greenland ice sheet documented by historical firn and ice temperature observations and machine learning

Recent warming trends of the Greenland ice sheet documented by historical firn and ice temperature observations and machine learning Baptiste Vandecrux, Robert S. Fausto, Jason E. Box, Federico Covi, Regine Hock, Åsa K. Rennermalm, Achim Heilig, Jakob Abermann, Dirk van As, Elisa Bjerre, Xavier Fettweis, Paul C. J. P. Smeets, Peter Kuipers Munneke, Michiel R. van den Broeke, Max Brils, Peter L. Langen, Ruth Mottram, and Andreas P. Ahlstrøm The Cryosphere, 18, 609–631, https://doi.org/10.5194/tc-18-609-2024, 2024 How fast is the Greenland ice sheet warming? In this study, we compiled 4500+ temperature measurements at 10 m below the ice sheet surface (T10m) from 1912 to 2022. We trained a machine learning model on these data and reconstructed T10m for the ice sheet during 1950–2022. After a slight cooling during 1950–1985, the ice sheet warmed at a rate of 0.7 °C per decade until 2022. Climate models showed mixed results compared to our observations and underestimated the warming in key regions.

Snow water equivalent retrieval over Idaho – Part 1: Using Sentinel-1 repeat-pass interferometry

Snow water equivalent retrieval over Idaho – Part 1: Using Sentinel-1 repeat-pass interferometry Shadi Oveisgharan, Robert Zinke, Zachary Hoppinen, and Hans Peter Marshall The Cryosphere, 18, 559–574, https://doi.org/10.5194/tc-18-559-2024, 2024 The seasonal snowpack provides water resources to billions of people worldwide. Large-scale mapping of snow water equivalent (SWE) with high resolution is critical for many scientific and economics fields. In this work we used the radar remote sensing interferometric synthetic aperture radar (InSAR) to estimate the SWE change between 2 d. The error in the estimated SWE change is less than 2 cm for in situ stations. Additionally, the retrieved SWE using InSAR is correlated with lidar snow depth. 

Extreme events of snow grain size increase in East Antarctica and their relationship with meteorological conditions

Extreme events of snow grain size increase in East Antarctica and their relationship with meteorological conditions Claudio Stefanini, Giovanni Macelloni, Marion Leduc-Leballeur, Vincent Favier, Benjamin Pohl, and Ghislain Picard The Cryosphere, 18, 593–608, https://doi.org/10.5194/tc-18-593-2024, 2024 Local and large-scale meteorological conditions have been considered in order to explain some peculiar changes of snow grains on the East Antarctic Plateau from 2000 to 2022, by using remote sensing observations and reanalysis. We identified some extreme grain size events on the highest ice divide, resulting from a combination of conditions of low wind speed and low temperature. Moreover, the beginning of seasonal grain growth has been linked to the occurrence of atmospheric rivers.

Melting ice core archives

Nature Geoscience, Published online: 12 February 2024; doi:10.1038/s41561-024-01385-6

Results from South Pole Telescope's new camera emerge

For more than five years, scientists at the South Pole Telescope in Antarctica have been observing the sky with an upgraded camera. The extended gaze toward the cosmos is picking up remnant light from the universe's early formation. Now researchers have analyzed an initial batch of data, publishing details in the journal Physical Review D. The results from this limited dataset hint at even more powerful future insights about the nature of our universe.

Ice cores provide first documentation of rapid Antarctic ice loss in the past

Researchers have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around eight thousand years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 meters -- that's more than the height of the Empire State Building -- in just under 200 years.

Evaluation of satellite methods for estimating supraglacial lake depth in southwest Greenland

Evaluation of satellite methods for estimating supraglacial lake depth in southwest Greenland Laura Melling, Amber Leeson, Malcolm McMillan, Jennifer Maddalena, Jade Bowling, Emily Glen, Louise Sandberg Sørensen, Mai Winstrup, and Rasmus Lørup Arildsen The Cryosphere, 18, 543–558, https://doi.org/10.5194/tc-18-543-2024, 2024 Lakes on glaciers hold large volumes of water which can drain through the ice, influencing estimates of sea level rise. To estimate water volume, we must calculate lake depth. We assessed the accuracy of three satellite-based depth detection methods on a study area in western Greenland and considered the implications for quantifying the volume of water within lakes. We found that the most popular method of detecting depth on the ice sheet scale has higher uncertainty than previously assumed.

Seasonal to decadal dynamics of supraglacial lakes on debris-covered glaciers in the Khumbu region, Nepal

Seasonal to decadal dynamics of supraglacial lakes on debris-covered glaciers in the Khumbu region, Nepal Lucas Zeller, Daniel McGrath, Scott W. McCoy, and Jonathan Jacquet The Cryosphere, 18, 525–541, https://doi.org/10.5194/tc-18-525-2024, 2024 In this study we developed methods for automatically identifying supraglacial lakes in multiple satellite imagery sources for eight glaciers in Nepal. We identified a substantial seasonal variability in lake area, which was as large as the variability seen across entire decades. These complex patterns are not captured in existing regional-scale datasets. Our findings show that this seasonal variability must be accounted for in order to interpret long-term changes in debris-covered glaciers.

Abrupt Holocene ice loss due to thinning and ungrounding in the Weddell Sea Embayment

Nature Geoscience, Published online: 08 February 2024; doi:10.1038/s41561-024-01375-8

Will this new solar maximum solve the puzzle of the sun's gamma-ray picture?

A new study, published in The Astrophysical Journal, has produced a compressed 14-year movie of the sun observed in gamma rays, a visualization tool which revealed that—contrary to the expected uniform distribution of these high energy photons—the solar disk can become brighter on the polar regions. This tendency for the sun's glow in the gamma rays to be dominant at the highest latitudes is evident during the peak of solar activity, as could be seen in June of 2014.

Wildlife Photographer of the Year People's Choice Award winner

A stunning image of a young polar bear drifting to sleep wins a wildlife-photographer competition

Improved monitoring of subglacial lake activity in Greenland

Improved monitoring of subglacial lake activity in Greenland Louise Sandberg Sørensen, Rasmus Bahbah, Sebastian B. Simonsen, Natalia Havelund Andersen, Jade Bowling, Noel Gourmelen, Alex Horton, Nanna B. Karlsson, Amber Leeson, Jennifer Maddalena, Malcolm McMillan, Anne Solgaard, and Birgit Wessel The Cryosphere, 18, 505–523, https://doi.org/10.5194/tc-18-505-2024, 2024 Under the right topographic and hydrological conditions, lakes may form beneath the large ice sheets. Some of these subglacial lakes are active, meaning that they periodically drain and refill. When a subglacial lake drains rapidly, it may cause the ice surface above to collapse, and here we investigate how to improve the monitoring of active subglacial lakes in Greenland by monitoring how their associated collapse basins change over time.

What happens now bird flu has reached the Antarctic? – podcast

The moment scientists had been dreading arrived late last year, when H5N1, or bird flu, was found for the first time in the Antarctic. Last week a king penguin on the island of South Georgia became the first in the region to be suspected to have died from the disease. The Guardian’s biodiversity reporter, Phoebe Weston, tells Ian Sample why researchers have said the spread of bird flu through the Antarctic’s penguin colonies could signal ‘one of the largest ecological disasters of modern times’

You can follow all the Guardian’s reporting on bird flu here

Study challenges the classical view of the origin of the Antarctic Circumpolar Current and warns of its vulnerability

The Circumpolar Current works as a regulator of the planet's climate. Its origins were thought to have caused the formation of the permanent ice in Antarctica about 34 million years ago. Now, a study has cast doubt on this theory, and has changed the understanding of how the ice sheet in Antarctic developed in the past, and what this could mean in the future as the planet's climate changes.

Vitamin B12 adaptability in Antarctic algae has implications for climate change, life in the Southern Ocean

The algae P. antarctica has two forms of the enzyme that makes the amino acid methionine, one needing B12, and one that is slower, but doesn't need it. This means it has the ability to adapt and survive with low B12 availability. The presence of the MetE gene in P. antarctica gives the algae the ability to adapt to lower vitamin B12 availability, giving it a potential advantage to bloom in the early austral spring when bacterial production is low. P. antarctica takes in the CO2 and releases oxygen through photosynthesis. Understanding its ability to grow in environments with low vitamin B12 availability can help climate modelers make more accurate predictions.

Nothing Swift about January’s Arctic sea ice

Arctic sea ice growth was slower than average through most of the month, but with extent slightly declining towards the end of the month. Antarctic sea ice extent returned to near-record daily lows after a brief excursion out of the … Continue reading →

'Catastrophic' flooding to hit California as bad weather continues

The "atmospheric rivers" causing the storms will linger on Monday as the state is pummelled by rain, wind and snow.

Atmospheric river: 'Life-threatening' storm lashes California with rain, wind and snow

Some residents were told to evacuate before "one of the most dramatic weather days in recent memory".

Pilotless drones being tested in Antarctica for use in scientific research

If tests are successful, Windracers Ultra UAV will be used for research such as surveying marine ecosystems and studying glaciers

Pilotless drones are being tested in Antarctica with the aim of using them to carry out scientific research.

A test crew has arrived at the largest British science facility on the continent, the Rothera Research Station.

Robot plane to map mysteries of wild Antarctica

The British Antarctic Survey hope the new technology will change what we know about global warming.

Ice and fire: Antarctic volcano may hold clues to life on Mars

On Deception Island in Antarctica, steam rises from the beaches, and glaciers dot the black slopes of what is actually an active volcano—a rare clash of ice and fire that provides clues to scientists about what life could look like on Mars.

Non-destructive multi-sensor core logging allows for rapid imaging and estimation of frozen bulk density and volumetric ice content in permafrost cores

Non-destructive multi-sensor core logging allows for rapid imaging and estimation of frozen bulk density and volumetric ice content in permafrost cores Joel Pumple, Alistair Monteath, Jordan Harvey, Mahya Roustaei, Alejandro Alvarez, Casey Buchanan, and Duane Froese The Cryosphere, 18, 489–503, https://doi.org/10.5194/tc-18-489-2024, 2024 Ice content is a critical variable in the context of thawing permafrost, and permafrost cores provide a means to measure the characteristics of frozen ground; however, these measurements are typically destructive and time intensive. Multi-sensor core logging (MSCL) provides a fast, non-destructive method to image permafrost cores, measure bulk density, and estimate ice content. The use of MSCL will improve existing digital permafrost archives by adding high-quality and reproducible data.

Permafrost alone holds back Arctic rivers -- and a lot of carbon

A new study provides the first evidence that the Arctic's frozen soil is the dominant force shaping Earth's northernmost rivers, confining them to smaller areas and shallower valleys than rivers to the south. But as climate change weakens Arctic permafrost, the researchers calculate that every 1 degree Celsius of global warming could release as much carbon as 35 million cars emit in a year as polar waterways expand and churn up the thawing soil.

Cloud- and ice-albedo feedbacks drive greater Greenland Ice Sheet sensitivity to warming in CMIP6 than in CMIP5

Cloud- and ice-albedo feedbacks drive greater Greenland Ice Sheet sensitivity to warming in CMIP6 than in CMIP5 Idunn Aamnes Mostue, Stefan Hofer, Trude Storelvmo, and Xavier Fettweis The Cryosphere, 18, 475–488, https://doi.org/10.5194/tc-18-475-2024, 2024 The latest generation of climate models (Coupled Model Intercomparison Project Phase 6 – CMIP6) warm more over Greenland and the Arctic and thus also project a larger mass loss from the Greenland Ice Sheet (GrIS) compared to the previous generation of climate models (CMIP5). Our work suggests for the first time that part of the greater mass loss in CMIP6 over the GrIS is driven by a difference in the surface mass balance sensitivity from a change in cloud representation in the CMIP6 models.

NASA to study effects of radio noise on lunar science

In February 2024, Intuitive Machines' IM-1 mission will launch to the moon's South Polar region, as part of NASA's Commercial Lunar Payload Services (CLPS) initiative. This mission is part of the CLPS ongoing effort to bring down the cost for science investigations and technology demonstrations going to the moon and to make them more routine in the lead-up to the Artemis landings later this decade.

More flights over Antarctica for Biomass and a bit of cricket

With ESA’s Biomass in the latter stages of development, two intrepid scientists are braving the cold in the icy reaches of Antarctica for two months to take measurements from the air and from the ground to help prepare for this new satellite mission. Here’s the next report from Jørgen Dall and Anders [...]

Massive taxidermy polar bear stolen in bizarre Canadian heist

The 12ft (3.6m) taxidermy bear was snatched from a Canadian resort during an opportune cold snap.