World's sea-ice falls to record low

The world's frozen oceans keep the planet cool, but they currently have less ice than ever recorded before.

Why polar bear fur doesn't freeze

A study in the journal Science Advances reveals how polar bears manage to get wet in the cold without their fur freezing.

Lake Mead Water Levels Drop Again as Snow Drought Takes Over Western U.S.

Learn more about the snow drought impacting the western U.S. and what that means for vital water sources.

Nanoplastics at lofty heights

Nanoplastics -- plastic particles smaller than 1 m -- are widely dispersed because of their low weight. A research team now shows the extent to which glaciers at an altitude of more than 3,000 m in the Alps are polluted by nanoplastics. The researchers relied on citizen science to collect the data. Mountaineers collected the samples on the glaciers.

Solar-powered device captures carbon dioxide from air to make sustainable fuel

Researchers have developed a reactor that pulls carbon dioxide directly from the air and converts it into sustainable fuel, using sunlight as the power source.

Research team identifies carbonate-dissolving microorganisms

A research team has shown that methanogens, micro-organisms ubiquitous in low-oxygen environments like aquifers, soil and even permafrost, can propel their growth by dissolving calcium carbonate, one of the Earth's most abundant minerals. The discovery paints a clearer picture of carbon flow through the environment and offers new information to guide bioenergy development.

Lava and smoke emerge from a snowy Mount Etna

Drone footage shows plumes of smoke and molten lava spewing from Europe's most active volcano.

NASA's polar ice experiment paves way for future moon missions

NASA's Polar Resources Ice Mining Experiment-1 (PRIME-1) is preparing to explore the moon's subsurface and analyze where lunar resources may reside.

Sentinel-1C demonstrates power to map land deformation

Launched just two months ago and still in the process of being commissioned for service, the Copernicus Sentinel-1C satellite is, remarkably, already showing how its radar data can be used to map the shape of Earth’s land surface with extreme precision.

These first cross-satellite ‘interferometry’ results assure its ability to monitor subsidence, uplift, glacier flow, and disasters such as landslides and earthquakes.

Amundsen Sea Embayment accumulation variability measured with global navigation satellite system interferometric reflectometry

Amundsen Sea Embayment accumulation variability measured with global navigation satellite system interferometric reflectometry Andrew O. Hoffman, Michelle L. Maclennan, Jan Lenaerts, Kristine M. Larson, and Knut Christianson The Cryosphere, 19, 713–730, https://doi.org/10.5194/tc-19-713-2025, 2025 Traditionally, glaciologists use global navigation satellite systems (GNSSs) to measure the surface elevation and velocity of glaciers to understand processes associated with ice flow. Using the interference of GNSS signals that bounce off of the ice sheet surface, we measure the surface height change near GNSS receivers in the Amundsen Sea Embayment (ASE). From surface height change, we infer daily accumulation rates that we use to understand the drivers of extreme precipitation in the ASE.

Arctic cyclones could be missing link in sea ice depletion models

A study gives possible insight into the underprediction of sea ice depletion and the formation of Arctic cyclones. The study could lead to more accurate weather and climate models and better forecasting of Arctic cyclones.

Astronomers unveil spectro-polarimetric properties of X-ray binary GX 9+1

Using the X-ray Polarimetry Explorer (IXPE) and Neutron star Interior Composition Explorer (NICER), Indian astronomers have observed an X-ray binary system known as GX 9+1. Results of the observational campaign, presented in a paper published Feb. 4 on the arXiv pre-print server, shed more light on the spectro-polarimetric properties of this system.

Physically based modelling of glacier evolution under climate change in the tropical Andes

Physically based modelling of glacier evolution under climate change in the tropical Andes Jonathan D. Mackay, Nicholas E. Barrand, David M. Hannah, Emily Potter, Nilton Montoya, and Wouter Buytaert The Cryosphere, 19, 685–712, https://doi.org/10.5194/tc-19-685-2025, 2025 We combine two globally capable glacier evolution models to include processes that are typically neglected but thought to control tropical glacier retreat (e.g. sublimation). We apply the model to Peru's Vilcanota-Urubamba Basin. The model captures observed glacier mass changes,but struggles with surface albedo dynamics. Projections show glacier mass shrinking to 17 % or 6 % of 2000 levels by 2100 under moderate- and high-emission scenarios, respectively.

Daily briefing: Why US scientists aren’t retiring

Nature, Published online: 12 February 2025; doi:10.1038/d41586-025-00483-8

How centuries of isolation shaped Greenlanders’ unique genetics

Nature, Published online: 12 February 2025; doi:10.1038/d41586-025-00443-2

Genetic data from Indigenous Greenlanders could help to narrow health-care gap

Nature, Published online: 12 February 2025; doi:10.1038/d41586-025-00091-6

Genetic architecture in Greenland is shaped by demography, structure and selection

Nature, Published online: 12 February 2025; doi:10.1038/s41586-024-08516-4

Model of Antarctica's water enhances sea level forecasts

Researchers have generated the first dataset of water flow beneath the entire Antarctic Ice Sheet, which will lead to more accurate projections of sea level rise. The team modeled Antarctica's subglacial environment. The dataset represents the researchers' best approximation of what the water flow underneath the ice sheet might currently look like. The results include numerous subglacial lakes developing below ice streams in both East and West Antarctica, and an extensive network of subglacial water channels that discharge large fluxes of water under many major glaciers.

An examination of changes in autumn Eurasian snow cover and its relationship with the winter Arctic Oscillation using 20th Century Reanalysis version 3

An examination of changes in autumn Eurasian snow cover and its relationship with the winter Arctic Oscillation using 20th Century Reanalysis version 3 Gareth J. Marshall The Cryosphere, 19, 663–683, https://doi.org/10.5194/tc-19-663-2025, 2025 Eurasian autumn snow cover (SC) can influence Northern Hemisphere weather in the following winter by affecting the Arctic Oscillation (AO) mode of atmospheric variability. Using data back to 1836, we show that there have been significant decreases in October and November SC. For the first time, we describe a robust relationship between September SC in northeastern Eurasia and the AO. In addition, the longer dataset reveals the temporal variability in previously identified SC–AO relationships.

Extreme precipitation associated with atmospheric rivers over West Antarctic ice shelves: insights from kilometre-scale regional climate modelling

Extreme precipitation associated with atmospheric rivers over West Antarctic ice shelves: insights from kilometre-scale regional climate modelling Ella Gilbert, Denis Pishniak, José Abraham Torres, Andrew Orr, Michelle Maclennan, Nander Wever, and Kristiina Verro The Cryosphere, 19, 597–618, https://doi.org/10.5194/tc-19-597-2025, 2025 We use three sophisticated climate models to examine extreme precipitation in a critical region of West Antarctica. We found that rainfall probably occurred during the two cases we examined and that it was generated by the interaction of air with steep topography. Our results show that kilometre-scale models are useful tools for exploring extreme precipitation in this region and that more observations of rainfall are needed.

The 2025 Snow Moon Will be Visible Before Valentine's Day — Here's What to Know

Learn about the upcoming snow moon that will happen on February 12, 2025, and how February sometimes doesn’t have a full moon.

New autonomous system to monitor Arctic's melting ice

Researchers have designed an alternative, autonomous observational method to monitor the Arctic's melting ice, which holds promise for improving the autonomy of marine vehicles, aiding in maritime missions, and gaining a deeper understanding of how melting Arctic sea ice affects marine ecosystems. Their conceptual design features a small waterplane area twin hull vessel that acts as a docking and charging station for autonomous underwater vehicles and unmanned aerial vehicles, using solar and turbine energy to enable continuous monitoring.

The Big Idea: how do our brains know what’s real?

From seeing things to hearing voices, there’s a finer line between hallucination and reality than you might suppose

When did you last hallucinate? “The visionary tendency is much more common among sane people than is generally suspected,” wrote the 19th-century psychologist Sir Francis Galton. Setting aside the vivid, often emotive, cinema of our dreams, we are all more vulnerable to “seeing things” than we might at first suppose.

Around four fifths of people who have recently been bereaved report an encounter with their loved one: most commonly a lively sense of their presence, but some hear, see or speak with them. Up to 60% of people who lose sight in later life see things that aren’t there, sometimes extravagant images such as the “two young men … wearing magnificent cloaks … their hats … trimmed with silver” who appeared in the first reported case of Charles Bonnet syndrome, as this phenomenon is known, before “dissolving” away. A 20-year-old woman blindfolded for 12 hours saw “cities, skies, kaleidoscopes, lions and sunsets so bright she could ‘barely look at them’”. After losing a limb, most people carry a “constant or inconstant phantom of the missing member”, as Weir Mitchell, the American neurologist who coined the term phantom limb after studying 90 cases from the American civil war, put it. Pilots on long flights, travellers through snowstorms and deserts, prisoners and hostages held in darkness; their restless brains are all prone to see the things of which they’re being deprived.

The Greenland Ice Sheet is fracturing faster than expected

Nature, Published online: 10 February 2025; doi:10.1038/d41586-025-00408-5

An Arctic 'beyond recognition' by 2100

Based on the current pledges of countries for limiting their emissions of greenhouse gases, global temperatures are projected to reach 2.7 degrees Celsius beyond pre-industrial levels by the end of this century. A new review paper highlights how this would dramatically reshape the Arctic, the fastest-warming region of Earth.

Earth from space: Snow-capped Swiss Alps

The ranges and valleys of the Swiss Alps stand out in this image captured by the Copernicus Sentinel-2 mission in December 2024.

Earth from Space: Snow-capped Swiss Alps

Image: The ranges and valleys of the Swiss Alps stand out in this image captured by the Copernicus Sentinel-2 mission in December 2024.

Physics-aware machine learning for glacier ice thickness estimation: a case study for Svalbard

Physics-aware machine learning for glacier ice thickness estimation: a case study for Svalbard Viola Steidl, Jonathan Louis Bamber, and Xiao Xiang Zhu The Cryosphere, 19, 645–661, https://doi.org/10.5194/tc-19-645-2025, 2025 Glacier ice thickness is difficult to measure directly but is essential for glacier evolution modelling. In this work, we employ a novel approach combining physical knowledge and data-driven machine learning to estimate the ice thickness of multiple glaciers in Spitsbergen, Barentsøya, and Edgeøya in Svalbard. We identify challenges for the physics-aware machine learning model and opportunities for improving the accuracy and physical consistency that would also apply to other geophysical tasks.

Formation and fate of freshwater on an ice floe in the Central Arctic

Formation and fate of freshwater on an ice floe in the Central Arctic Madison M. Smith, Niels Fuchs, Evgenii Salganik, Donald K. Perovich, Ian Raphael, Mats A. Granskog, Kirstin Schulz, Matthew D. Shupe, and Melinda Webster The Cryosphere, 19, 619–644, https://doi.org/10.5194/tc-19-619-2025, 2025 The fate of freshwater from Arctic sea ice and snowmelt impacts interactions of the atmosphere, sea ice, and ocean. We complete a comprehensive analysis of datasets from a 2020 central Arctic field campaign to understand the drivers of the sea ice freshwater budget and the fate of this water. Over half of the freshwater comes from surface melt, and a majority fraction is incorporated into the ocean. Results suggest that the representation of melt ponds is a key area for future development.

Ice streams move due to tiny ice quakes

An international team of researchers has shown that countless tiny ice quakes take place in one of Greenland's mightiest ice streams. This finding will allow the flowing of the ice sheet and associated changes in sea level to be estimated more accurately.

In Greenland, the Ice Doesn’t Just Flow, It Quivers and Quakes

By using a fiber-optic cable to detect tiny vibrations a mile below the surface, scientists discovered a surprising way that ice sheets move.

Hole drilled into Greenland's heart reveals ice ready to slide into the sea

Unique drilling project has ominous implications for sea-level rise

An Antarctic Fossil From 69 Million Years Ago Reveals Earth’s Early Birds

Learn more about Vegavis iaai, an ancient ancestor of modern-day ducks, and one of the earliest modern birds ever discovered.

The Search for the Original Silly Goose in the Fossil Record

Some paleontologists think that fossils recovered from Antarctica are evidence of birds similar to modern geese and ducks that lived alongside the dinosaurs.

As Scandinavian peninsula rises from sea, new satellite data show gravity changes

Bouncing back from under the weight of Ice Age glaciers which have long since vanished, the Nordic region land mass is slowly rising above sea level.

An ancestor of ducks and geese paddled and dove alongside dinosaurs in Antarctica

Exquisite, fossilized skull sheds light on the evolutionary origins of waterfowl

Historical snow measurements in the central and southern Apennine Mountains: climatology, variability, and trend

Historical snow measurements in the central and southern Apennine Mountains: climatology, variability, and trend Vincenzo Capozzi, Francesco Serrapica, Armando Rocco, Clizia Annella, and Giorgio Budillon The Cryosphere, 19, 565–595, https://doi.org/10.5194/tc-19-565-2025, 2025 This “journey through time” discovers historical information about snow precipitation in the Italian Apennines. In this area, in the second half of the past century, a gradual decline in snow persistence on the ground, as well as in the frequency of occurrence of snowfall events, has been observed, especially in sites located above 1000 m above sea level. The old data rescued in this study strongly enhance our knowledge about past snowfall variability and climate in the Mediterranean area.

Why polar bear fur doesn't freeze

A new study reveals how polar bears manage to get wet in the cold without freezing.

Why polar bear fur doesn't freeze

New research finds grease that coats polar bear fur contains a specialized mixture of chemicals that make it resistant to freezing

Cretaceous Antarctic bird skull elucidates early avian ecological diversity

Nature, Published online: 05 February 2025; doi:10.1038/s41586-024-08390-0

Topological water-wave structures manipulating particles

Nature, Published online: 05 February 2025; doi:10.1038/s41586-024-08384-y

Fossil bird skull suggests Antarctic waterfowl survived Cretaceous mass extinction

Nature, Published online: 05 February 2025; doi:10.1038/d41586-024-04153-z

ISMIP6-based Antarctic projections to 2100: simulations with the BISICLES ice sheet model

ISMIP6-based Antarctic projections to 2100: simulations with the BISICLES ice sheet model James F. O'Neill, Tamsin L. Edwards, Daniel F. Martin, Courtney Shafer, Stephen L. Cornford, Hélène L. Seroussi, Sophie Nowicki, Mira Adhikari, and Lauren J. Gregoire The Cryosphere, 19, 541–563, https://doi.org/10.5194/tc-19-541-2025, 2025 We use an ice sheet model to simulate the Antarctic contribution to sea level over the 21st century under a range of future climates and varying how sensitive the ice sheet is to different processes. We find that ocean temperatures increase and more snow falls on the ice sheet under stronger warming scenarios. When the ice sheet is sensitive to ocean warming, ocean melt-driven loss exceeds snowfall-driven gains, meaning that the sea level contribution is greater with more climate warming.

Buffalo Bills Fans Have It Tough, Especially in Antarctica

Research scientists in remote locations need to get creative in order to follow their favorite teams, even when they don’t like the outcomes.

Why scientists are counting tiny marine creatures from Space

Differences in seawater colour could reveal how tiny Antarctic creatures are faring in a warming world.

Temperature, rainfall and tides speed glacier flow on a daily basis

Detailed study of a Greenland glacier's flow rate reveals the impact of environmental conditions.

More, bigger crevasses open up in Greenland ice sheet, threatening increased sea level rise

More crevasse activity could lead to positive feedback loop threatening Greenland glacier's stability.

Greenland ice sheet cracking more rapidly than ever, study shows

Crevasses increasing in size and depth in response to climate breakdown, Durham University researchers find

The Greenland ice sheet – the second largest body of ice in the world – is cracking more rapidly than ever before as a response to climate breakdown, a study has found.

Researchers used 8,000 three-dimensional surface maps from high-resolution commercial satellite imagery to assess the evolution of cracks in the surface of the ice sheet between 2016 and 2021.

Planet party and snow moon to shine over California: When to watch the sky

Californians watching the sky in February have the chance to view a parade of planets and a snow moon. The planetary alignment that began in January will continue into February, according to AccuWeather.

'Genocide against Greenland': The country's dark history - and does it want Trump?

The US president's talk about taking control has come at a time when many on the island are already considering their future

Increased crevassing across accelerating Greenland Ice Sheet margins

Nature Geoscience, Published online: 03 February 2025; doi:10.1038/s41561-024-01636-6

Ice speed of a Greenlandic tidewater glacier modulated by tide, melt, and rain

Ice speed of a Greenlandic tidewater glacier modulated by tide, melt, and rain Shin Sugiyama, Shun Tsutaki, Daiki Sakakibara, Izumi Asaji, Ken Kondo, Yefan Wang, Evgeny Podolskiy, Guillaume Jouvet, and Martin Funk The Cryosphere, 19, 525–540, https://doi.org/10.5194/tc-19-525-2025, 2025 We report flow speed variations near the front of a tidewater glacier in Greenland. Ice flow near the glacier front is crucial for the mass loss of the Greenland ice sheet, but in situ data are hard to obtain. Our unique in situ GPS data revealed fine details of short-term speed variations associated with melting, ocean tides, and rain. The results are important for understanding the response of tidewater glaciers to changing environments, such as warming, more frequent rain, and ice thinning.

Subglacial discharge effects on basal melting of a rotating, idealized ice shelf

Subglacial discharge effects on basal melting of a rotating, idealized ice shelf Irena Vaňková, Xylar Asay-Davis, Carolyn Branecky Begeman, Darin Comeau, Alexander Hager, Matthew Hoffman, Stephen F. Price, and Jonathan Wolfe The Cryosphere, 19, 507–523, https://doi.org/10.5194/tc-19-507-2025, 2025 We study the effect of subglacial discharge on basal melting for Antarctic ice shelves. We find that the results from previous studies of vertical ice fronts and two-dimensional ice tongues do not translate to the rotating ice-shelf framework. The melt rate dependence on discharge is stronger in the rotating framework. Further, there is a substantial melt-rate sensitivity to the location of the discharge along the grounding line relative to the directionality of the Coriolis force.

Groundwater in Arctic is delivering more carbon into the ocean than was previously known

A relatively small amount of groundwater trickling through Alaska's tundra is releasing huge quantities of carbon into the ocean, where it can contribute to climate change.

Polar bear population decline the direct result of extended 'energy deficit' due to lack of food

U of T Scarborough researchers have directly linked population decline in polar bears living in Western Hudson Bay to shrinking sea ice caused by climate change.

Antarctic fast ice secrets

Scientists have successfully analyzed more than 30 years of vital data on the thickness of landfast sea ice in Antarctica's McMurdo Sound, which will prove useful to measure future impacts of climate change.

Bad hair bears! Greasy hair gives polar bears fur with anti-icing properties

Scientists have discovered the anti-icing secret of polar bear fur -- something that allows one of the planet's most iconic animals to survive and thrive in one of its most punishing climates. That secret? Greasy hair. After some polar sleuthing, which involved scrutiny of hair collected from six polar bears in the wild, the scientists homed in on the hair 'sebum' (or grease) as the all-important protectant. This sebum, which is made up of cholesterol, diacylglycerols, and fatty acids, makes it very hard for ice to attach to their fur. While this finding sheds fascinating new light on our understanding of polar bear -- and even Inuit -- ecology, it may also have a suite of unrelated applications, with a similar concoction of artificially made sebum promising to be useful as an anti-ice surface coating, or in next-gen ski skins used by skiers and snowboarders.

An Unwashed, Greasy Hair Day Actually Keeps Polar Bears Ice-Free

Learn more about polar bear sebum, the oil on their fur that prevents ice from sticking to them, and how it could be used to replace certain PFAS.

Polar bear fur has a built-in deicing feature

An analysis of the Arctic animals’ fur reveals chemical clues to how they stay ice-free

Pressurised water flow in fractured permafrost rocks revealed by borehole temperature, electrical resistivity tomography, and piezometric pressure

Pressurised water flow in fractured permafrost rocks revealed by borehole temperature, electrical resistivity tomography, and piezometric pressure Maike Offer, Samuel Weber, Michael Krautblatter, Ingo Hartmeyer, and Markus Keuschnig The Cryosphere, 19, 485–506, https://doi.org/10.5194/tc-19-485-2025, 2025 We present a unique long-term dataset of measurements of borehole temperature, repeated electrical resistivity tomography, and piezometric pressure to investigate the complex seasonal water flow in permafrost rockwalls. Our joint analysis shows that permafrost rocks are subjected to enhanced pressurised water flow during the thaw period, resulting in push-like warming events and long-lasting rock temperature regime changes.  

Separating snow and ice melt using water stable isotopes and glacio-hydrological modelling: towards improving the application of isotope analyses in highly glacierized catchments

Separating snow and ice melt using water stable isotopes and glacio-hydrological modelling: towards improving the application of isotope analyses in highly glacierized catchments Tom Müller, Mauro Fischer, Stuart N. Lane, and Bettina Schaefli The Cryosphere, 19, 423–458, https://doi.org/10.5194/tc-19-423-2025, 2025 Based on extensive field observations in a highly glacierized catchment in the Swiss Alps, we develop a combined isotopic and glacio-hydrological model. We show that water stable isotopes may help to better constrain model parameters, especially those linked to water transfer. However, we highlight that separating snow and ice melt for temperate glaciers based on isotope mixing models alone is not advised and should only be considered if their isotopic signatures have clearly different values.

High-resolution 4D electrical resistivity tomography and below-ground point sensor monitoring of High Arctic deglaciated sediments capture zero-curtain effects, freeze–thaw transitions, and mid-winter thawing

High-resolution 4D electrical resistivity tomography and below-ground point sensor monitoring of High Arctic deglaciated sediments capture zero-curtain effects, freeze–thaw transitions, and mid-winter thawing Mihai O. Cimpoiasu, Oliver Kuras, Harry Harrison, Paul B. Wilkinson, Philip Meldrum, Jonathan E. Chambers, Dane Liljestrand, Carlos Oroza, Steven K. Schmidt, Pacifica Sommers, Lara Vimercati, Trevor P. Irons, Zhou Lyu, Adam Solon, and James A. Bradley The Cryosphere, 19, 401–421, https://doi.org/10.5194/tc-19-401-2025, 2025 Young Arctic sediments, uncovered by retreating glaciers, are in continuous development, shaped by how water infiltrates and is stored in the near subsurface. Harsh weather conditions at high latitudes make direct observation of these environments very difficult. To address this, we deployed two automated sensor installations in August 2021 on a glacier forefield in Svalbard. These sensors recorded continuously for 1 year, revealing unprecedented images of the ground’s freeze–thaw transition.

Benchmarking passive-microwave-satellite-derived freeze–thaw datasets

Benchmarking passive-microwave-satellite-derived freeze–thaw datasets Annett Bartsch, Xaver Muri, Markus Hetzenecker, Kimmo Rautiainen, Helena Bergstedt, Jan Wuite, Thomas Nagler, and Dmitry Nicolsky The Cryosphere, 19, 459–483, https://doi.org/10.5194/tc-19-459-2025, 2025 We developed a robust freeze–thaw detection approach, applying a constant threshold to Copernicus Sentinel-1 data that is suitable for tundra regions. All global, coarser-resolution products, tested with the resulting benchmarking dataset, are of value for freeze–thaw retrieval, although differences were found depending on the seasons, particularly during the spring and autumn transition.

Enhanced energy storage in antiferroelectrics via antipolar frustration

Nature, Published online: 29 January 2025; doi:10.1038/s41586-024-08505-7

Antarctic ice shelf kept its cool during the last interglacial period

Nature, Published online: 29 January 2025; doi:10.1038/d41586-025-00190-4

The Ronne Ice Shelf survived the last interglacial

Nature, Published online: 29 January 2025; doi:10.1038/s41586-024-08394-w

A Methane-Spewing Mud Volcano Gives Sanctuary to Arctic Seafloor Species

Learn about the Borealis Mud Volcano on the Arctic seafloor and its role in maintaining biodiversity, which is driven by methane emissions.

Danish PM in whirlwind EU trip as Greenland unease grows

The Danish PM's tour of three capitals betrayed the nervousness felt in Denmark over Trump's repeated comments.

Mapping Antarctica's hidden ice-free lands: a blueprint for conservation

Researchers unveil a new map and classification system that will help protect the unique plants and animals of Earth's most remote and fragile continent.

Antarctic ice sheet faces 'death by a thousand cuts'

Smaller calving events, not large icebergs, drive Antarctic ice sheet loss.

Brief communication: Monitoring snow depth using small, cheap, and easy-to-deploy snow–ground interface temperature sensors

Brief communication: Monitoring snow depth using small, cheap, and easy-to-deploy snow–ground interface temperature sensors Claire L. Bachand, Chen Wang, Baptiste Dafflon, Lauren N. Thomas, Ian Shirley, Sarah Maebius, Colleen M. Iversen, and Katrina E. Bennett The Cryosphere, 19, 393–400, https://doi.org/10.5194/tc-19-393-2025, 2025 Temporally continuous snow depth estimates are important for understanding changing snow patterns and impacts on frozen ground in the Arctic. In this work, we developed an approach to predict snow depth from variability in snow–ground interface temperature using small temperature sensors that are cheap and easy to deploy. This new technique enables spatially distributed and temporally continuous snowpack monitoring that has not previously been possible.

Evidence of active subglacial lakes under a slowly moving coastal region of the Antarctic Ice Sheet

Evidence of active subglacial lakes under a slowly moving coastal region of the Antarctic Ice Sheet Jennifer F. Arthur, Calvin Shackleton, Geir Moholdt, Kenichi Matsuoka, and Jelte van Oostveen The Cryosphere, 19, 375–392, https://doi.org/10.5194/tc-19-375-2025, 2025 Lakes can form beneath the large ice sheets and can influence ice-sheet dynamics and stability. Some of these subglacial lakes are active, meaning that they periodically drain and refill. Here we report seven new active subglacial lakes close to the Antarctic Ice Sheet margin using satellite measurements of ice surface height changes in a region where little was known previously. These findings improve our understanding of subglacial hydrology and will help refine subglacial hydrological models.

History and dynamics of Fennoscandian Ice Sheet retreat, contemporary ice-dammed lake evolution, and faulting in the Torneträsk area, northwestern Sweden

History and dynamics of Fennoscandian Ice Sheet retreat, contemporary ice-dammed lake evolution, and faulting in the Torneträsk area, northwestern Sweden Karlijn Ploeg and Arjen P. Stroeven The Cryosphere, 19, 347–373, https://doi.org/10.5194/tc-19-347-2025, 2025 Mapping of glacial landforms using lidar data shows that the retreating margin of the Fennoscandian Ice Sheet dammed a series of lakes in the Torneträsk Basin during deglaciation. These lakes were more extensive than previously thought and produced outburst floods. We show that sections of the Pärvie Fault, the longest glacially activated fault of Sweden, ruptured multiple times and during the existence of ice-dammed lake Torneträsk.

Denmark to spend billions more on Arctic security

The move comes after President Donald Trump said he wants to acquire Greenland, an autonomous Danish territory.

How animal poop helps ecosystems adapt to climate change

Relatives of the llama are dropping dung as they venture into higher elevations in the Andes Mountains, providing a nutrient-rich environment for life to thrive despite glacier loss.

Unraveling the connection between Canadian wildfires and Arctic ice clouds

Ice nucleating particles as a kind of aerosols have a significant impact on the Arctic climate by promoting the formation of ice clouds at a temperature above -- 38 degrees Celsius. Wildfires in mid-latitudinal areas are a major source of these aerosols. However, a direct observation of wildfire-emitted aerosols facilitating ice cloud formation has never been documented. Now, using field and climate data, scientists have linked aerosols emitted by Canadian wildfires in 2023 to the formation of ice clouds over the Arctic Ocean.

Snow depth estimation on leadless landfast ice using Cryo2Ice satellite observations

Snow depth estimation on leadless landfast ice using Cryo2Ice satellite observations Monojit Saha, Julienne Stroeve, Dustin Isleifson, John Yackel, Vishnu Nandan, Jack Christopher Landy, and Hoi Ming Lam The Cryosphere, 19, 325–346, https://doi.org/10.5194/tc-19-325-2025, 2025 Snow on sea ice is vital for near-shore sea ice geophysical and biological processes. Past studies have measured snow depths using the satellite altimeters Cryosat-2 and ICESat-2 (Cryo2Ice), but estimating sea surface height from leadless landfast sea ice remains challenging. Snow depths from Cryo2Ice are compared to in situ data after adjusting for tides. Realistic snow depths are retrieved, but differences in roughness, satellite footprints, and snow geophysical properties are identified.

Inside the race for Greenland's mineral wealth

The territory's untapped mineral wealth has caught the eye of both mining firms and Donald Trump.

Here's why Trump's pursuit of Greenland is really about the control over the Arctic

According to experts, Greenland is "ground zero for how the Arctic has become more geopolitically and strategically significant."

Trump says he believes US will 'get Greenland'

The president told reporters the island's 57,000 residents "want to be with us".

Assessing the suitability of sites near Pine Island Glacier for subglacial bedrock drilling aimed at detecting Holocene retreat–readvance

Assessing the suitability of sites near Pine Island Glacier for subglacial bedrock drilling aimed at detecting Holocene retreat–readvance Joanne S. Johnson, John Woodward, Ian Nesbitt, Kate Winter, Seth Campbell, Keir A. Nichols, Ryan A. Venturelli, Scott Braddock, Brent M. Goehring, Brenda Hall, Dylan H. Rood, and Greg Balco The Cryosphere, 19, 303–324, https://doi.org/10.5194/tc-19-303-2025, 2025 Determining where and when the Antarctic ice sheet was smaller than present requires recovery and exposure dating of subglacial bedrock. Here we use ice sheet model outputs and field data (geological and glaciological observations, bedrock samples, and ground-penetrating radar) to assess the suitability for subglacial drilling of sites in the Hudson Mountains, West Antarctica. We find that no sites are perfect, but two are feasible, with the most suitable being Winkie Nunatak (74.86°S, 99.77°W).

New Research Finds Potential Alternative to Abortion Pill Mifepristone

The research could further complicate the polarized politics of abortion because the drug in the study is the key ingredient in a pill used for emergency contraception.

Present-day mass loss rates are a precursor for West Antarctic Ice Sheet collapse

Present-day mass loss rates are a precursor for West Antarctic Ice Sheet collapse Tim van den Akker, William H. Lipscomb, Gunter R. Leguy, Jorjo Bernales, Constantijn J. Berends, Willem Jan van de Berg, and Roderik S. W. van de Wal The Cryosphere, 19, 283–301, https://doi.org/10.5194/tc-19-283-2025, 2025 In this study, we present an improved way of representing ice thickness change rates in an ice sheet model. We apply this method using two ice sheet models of the Antarctic Ice Sheet. We found that the two largest outlet glaciers on the Antarctic Ice Sheet, Thwaites Glacier and Pine Island Glacier, will collapse without further warming on a timescale of centuries. This would cause a sea level rise of about 1.2 m globally.

Permafrost Thaw and Wildfires Are Raising CO2 Emissions in Arctic Tundras

Learn about hotspots in tundras and boreal forests that are releasing higher level of carbon dioxide, altering the carbon balance in the world's coldest regions.

PUNCH spacecraft make final pit stop before launch

Four small suitcase-sized spacecraft, designed and built by Southwest Research Institute, have made a final Earth-side pit stop at Vandenberg Space Force Base in California. NASA's Polarimeter to Unify the Corona and Heliosphere (PUNCH) mission is sharing a ride to space with the Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer (SPHEREx) observatory.

Snow flurries are rare in US south – now a blizzard has hit

Snow and freezing rain hits parts of the deep south, closing highways and airports and prompting a first-ever blizzard warning in southwest Louisiana.

Creep enhancement and sliding in a temperate, hard-bedded alpine glacier

Creep enhancement and sliding in a temperate, hard-bedded alpine glacier Juan-Pedro Roldán-Blasco, Adrien Gilbert, Luc Piard, Florent Gimbert, Christian Vincent, Olivier Gagliardini, Anuar Togaibekov, Andrea Walpersdorf, and Nathan Maier The Cryosphere, 19, 267–282, https://doi.org/10.5194/tc-19-267-2025, 2025 The flow of glaciers and ice sheets results from ice deformation and basal sliding driven by gravitational forces. Quantifying the rate at which ice deforms under its own weight is critical for assessing glacier evolution. This study uses borehole instrumentation in an Alpine glacier to quantify ice deformation and constrain ice viscosity in a natural setting. Our results show that the viscosity of ice at 0 °C is largely influenced by interstitial liquid water, which enhances ice deformation.

Large study broadens view of the genetic landscape of bipolar disorder

Nature, Published online: 22 January 2025; doi:10.1038/d41586-025-00101-7

Field–particle energy transfer during chorus emissions in space

Nature, Published online: 22 January 2025; doi:10.1038/s41586-024-08402-z

Genomics yields biological and phenotypic insights into bipolar disorder

Nature, Published online: 22 January 2025; doi:10.1038/s41586-024-08468-9

Extreme climate pushed thousands of lakes in West Greenland 'across a tipping point,' study finds

Following two months of record heat and precipitation in fall 2022, an estimated 7,500 lakes in West Greenland turned brown, began emitting carbon and decreased in water quality in less than a year. The spike in temperatures caused the precipitation to fall as rain instead of snow. The heat also caused permafrost to thaw, releasing an abundance of carbon, iron, magnesium and other elements that the rain washed into the lakes. Researchers found a decrease in phytoplankton that absorb carbon dioxide from the atmosphere through photosynthesis within the lakes, and an increase in plankton that break down and release carbon. Instead of sequestering carbon dioxide in the summer, the lakes have become a source of it, with a 350% increase in the flux of this greenhouse gas from them.

Wildfires offset the increasing but spatially heterogeneous Arctic–boreal CO₂ uptake

Nature Climate Change, Published online: 21 January 2025; doi:10.1038/s41558-024-02234-5

Wave erosion, frontal bending, and calving at Ross Ice Shelf

Wave erosion, frontal bending, and calving at Ross Ice Shelf Nicolas B. Sartore, Till J. W. Wagner, Matthew R. Siegfried, Nimish Pujara, and Lucas K. Zoet The Cryosphere, 19, 249–265, https://doi.org/10.5194/tc-19-249-2025, 2025 We investigate how waves may erode the front of Antarctica's largest ice shelf, Ross Ice Shelf, and how this results in bending forces that can cause deformation of the near-front shelf and trigger intermediate-scale calving (with icebergs of lengths ∼ 100 m). We compare satellite observations to theoretical estimates of erosion and ice shelf bending in order to better understand the processes underlying this type of calving and its role in the overall ice shelf mass flux.

Five decades of Abramov glacier dynamics reconstructed with multi-sensor optical remote sensing

Five decades of Abramov glacier dynamics reconstructed with multi-sensor optical remote sensing Enrico Mattea, Etienne Berthier, Amaury Dehecq, Tobias Bolch, Atanu Bhattacharya, Sajid Ghuffar, Martina Barandun, and Martin Hoelzle The Cryosphere, 19, 219–247, https://doi.org/10.5194/tc-19-219-2025, 2025 We reconstruct the evolution of terminus position, ice thickness, and surface flow velocity of the reference Abramov glacier (Kyrgyzstan) from 1968 to present. We describe a front pulsation in the early 2000s and the multi-annual present-day buildup of a new pulsation. Such dynamic instabilities can challenge the representativity of Abramov as a reference glacier. For our work we used satellite‑based optical remote sensing from multiple platforms, including recently declassified archives.

Earth from Space: Frozen borders

Image: This Copernicus Sentinel-2 image captures the borders between North and South Dakota and Minnesota blanketed with snow and ice.

Benchmarking of snow water equivalent (SWE) products based on outcomes of the SnowPEx+ Intercomparison Project

Benchmarking of snow water equivalent (SWE) products based on outcomes of the SnowPEx+ Intercomparison Project Lawrence Mudryk, Colleen Mortimer, Chris Derksen, Aleksandra Elias Chereque, and Paul Kushner The Cryosphere, 19, 201–218, https://doi.org/10.5194/tc-19-201-2025, 2025 We evaluate and rank 23 different datasets on their ability to accurately estimate historical snow amounts. The evaluation uses new a set of surface snow measurements with improved spatial coverage, enabling evaluation across both mountainous and nonmountainous regions. Performance measures vary tremendously across the products: while most perform reasonably in nonmountainous regions, accurate representation of snow amounts in mountainous regions and of historical trends is much more variable.

Greenland’s melting ice is clearing the way for a mineral ‘gold rush’

Greenland, a vast but sparsely populated Arctic island, has been transformed by the climate crisis in recent decades.

How to be a brilliant ally to your neurodivergent lab mate

Nature, Published online: 17 January 2025; doi:10.1038/d41586-025-00125-z

Thawing permafrost threatens up to three million people in Arctic regions

In an interdisciplinary and transdisciplinary study, an international team examined the social risks for Arctic regions associated with thawing permafrost. They identified five key risks related to infrastructure, transport and supply, water quality, food security and health. The scientists found that the thawing permafrost posed an increased risk of exposure to infectious diseases and release of contaminants, and interruptions of supply routes.

Speleothem and ice cores: Natural climate archives offer new insights into the climate history of central Europe

The synchronization of data from two natural climate archives -- a speleothem from the Herbstlabyrinth Cave in Hesse (Germany) and ice cores from Greenland -- offers new insights into the chronology of abrupt climate changes in Central Europe. According to the analysis, the devastating eruption of the Laacher See volcano in what is now Rhineland-Palatinate occurred earlier than previously assumed and hence could not have triggered the sudden-onset cold period of approximately 13,000 years ago, geoscientists have found.

How satellite imagery can help monitor dangerous lakes formed by glacier surges near high-mountain communities

A new study analyzing a lake formed by a glacier surge in the Karakoram Mountains has revealed how satellite images can be used to monitor the potential for lake drainage hazards.

Pioneering research exposes huge loss of glaciers in one of the fastest-warming places on Earth

A new study has revealed the alarming extent glaciers have shrunk over the past 40 years in a global warming hotspot -- and the biggest retreat has occurred in recent years.

Up to Greenland to decide its future, Danish PM tells Trump

In her call with Trump, Mette Frederiksen also reiterated the Greenland PM's comments that it was "not for sale"

Surface processes and drivers of the snow water stable isotopic composition at Dome C, East Antarctica – a multi-dataset and modelling analysis

Surface processes and drivers of the snow water stable isotopic composition at Dome C, East Antarctica – a multi-dataset and modelling analysis Inès Ollivier, Hans Christian Steen-Larsen, Barbara Stenni, Laurent Arnaud, Mathieu Casado, Alexandre Cauquoin, Giuliano Dreossi, Christophe Genthon, Bénédicte Minster, Ghislain Picard, Martin Werner, and Amaëlle Landais The Cryosphere, 19, 173–200, https://doi.org/10.5194/tc-19-173-2025, 2025 The role of post-depositional processes taking place at the ice sheet's surface on the water stable isotope signal measured in polar ice cores is not fully understood. Using field observations and modelling results, we show that the original precipitation isotopic signal at Dome C, East Antarctica, is modified by post-depositional processes and provide the first quantitative estimation of their mean impact on the isotopic signal observed in the snow.

Spectral induced polarization survey for the estimation of hydrogeological parameters in an active rock glacier

Spectral induced polarization survey for the estimation of hydrogeological parameters in an active rock glacier Clemens Moser, Umberto Morra di Cella, Christian Hauck, and Adrián Flores Orozco The Cryosphere, 19, 143–171, https://doi.org/10.5194/tc-19-143-2025, 2025 We use electrical conductivity and induced polarization in an imaging framework to quantify hydrogeological parameters in the active Gran Sometta rock glacier. The results show high spatial variability in the hydrogeological parameters across the rock glacier and are validated by saltwater tracer tests coupled with 3D electrical conductivity imaging. Hydrogeological information was linked to kinematic data to further investigate its role in rock glacier movement.

From snowy cities to Mexican border - Trump deportations loom

'Do it the right way' Texas border residents tell migrants, while Chicago neighbourhoods prepare for raids.

Million-Year-Old Snow Leopard Bones Help Explain Their Rule During the Ice Age

Rare fossils challenge assumptions about how the big cats thrived in a challenging environment.

'My country is in crisis': A divided South Korea grapples with Yoon's arrest

The country is deeply polarised by the president's attempt to impose martial law.

Trump is fixated on Greenland — a vast Arctic island with massive resource potential

Mining executives and researchers describe the island's massive resource potential as an "enormous opportunity."

Atop the Oregon Cascades, team finds a huge buried aquifer

Scientists have mapped the amount of water stored beneath volcanic rocks at the crest of the central Oregon Cascades and found an aquifer many times larger than previously estimated -- at least 81 cubic kilometers. The finding has implications for the way scientists and policymakers think about water in the region -- an increasingly urgent issue across the Western United States as climate change reduces snowpack, intensifies drought and strains limited resources.

A hybrid ice-mélange model based on particle and continuum methods

A hybrid ice-mélange model based on particle and continuum methods Saskia Kahl, Carolin Mehlmann, and Dirk Notz The Cryosphere, 19, 129–141, https://doi.org/10.5194/tc-19-129-2025, 2025 Ice mélange, a mixture of sea ice and icebergs, can impact sea-ice–ocean interactions. But climate models do not yet represent it due to computational limits. To address this shortcoming and include ice mélange into climate models, we suggest representing icebergs as particles. We integrate their feedback into mathematical equations used to model the sea-ice motion in climate models. The setup is computationally efficient due to the iceberg particle usage and enables a realistic representation.

Researchers in Antarctica find ice from a million years ago

Scientists in Antarctica have dug out ice that can be from as far back as 1.2 million years. NPR's Ayesha Rascoe talks to researcher Carlo Barbante, about what he hopes to learn from the ice.

Trump threats cast ominous shadow over icy fjords of Greenland

In the isolated settlement of Kapisillit, Greenlanders tell the BBC's Fergal Keane Donald Trump is welcome to visit - "but that's it".

Trump wants to take Greenland: Four ways this saga could go

The BBC investigates possible scenarios for the huge Arctic territory's future as the US president-elect talks about taking control of it.

Passengers evacuate plane on snowy tarmac amid storm

The Delta flight, with more than 200 passengers on board, was suspended shortly after takeoff due to engine issues.

Modelling GNSS-observed seasonal velocity changes of the Ross Ice Shelf, Antarctica, using the Ice-sheet and Sea-level System Model (ISSM)

Modelling GNSS-observed seasonal velocity changes of the Ross Ice Shelf, Antarctica, using the Ice-sheet and Sea-level System Model (ISSM) Francesca Baldacchino, Nicholas R. Golledge, Mathieu Morlighem, Huw Horgan, Alanna V. Alevropoulos-Borrill, Alena Malyarenko, Alexandra Gossart, Daniel P. Lowry, and Laurine van Haastrecht The Cryosphere, 19, 107–127, https://doi.org/10.5194/tc-19-107-2025, 2025 Understanding how the Ross Ice Shelf flow is changing in a warming world is important for predicting ice sheet change. Field measurements show clear intra-annual variations in ice flow; however, it is unclear what mechanisms drive this variability. We show that local perturbations in basal melt can have a significant impact on ice flow speed, but a combination of forcings is likely driving the observed variability in ice flow.

Updated Arctic melt pond fraction dataset and trends 2002–2023 using ENVISAT and Sentinel-3 remote sensing data

Updated Arctic melt pond fraction dataset and trends 2002–2023 using ENVISAT and Sentinel-3 remote sensing data Larysa Istomina, Hannah Niehaus, and Gunnar Spreen The Cryosphere, 19, 83–105, https://doi.org/10.5194/tc-19-83-2025, 2025 Melt water puddles, or melt ponds on top of the Arctic sea ice, are a good measure of the Arctic climate state. In the context of recent climate warming, the Arctic has warmed about 4 times faster than the rest of the world, and a long-term dataset of the melt pond fraction is needed to be able to model the future development of the Arctic climate. We present such a dataset, produce 2002–2023 trends and highlight a potential melt regime shift with drastic regional trends of + 20 % per decade.

Danes struggle with response to Trump Greenland threat

Copenhagen's grey winter skies match the mood among politicians and business leaders in the face of a crisis.

Researchers use lab data to rewrite equation for deformation, flow of watery glacier ice

Laboratory experiments designed to deform ice at its pressure-melting temperature were like grabbing a bagel at the top and the bottom, then twisting the two halves to smear the cream cheese in the middle, according to new research. The resulting data could lead to more accurate models of temperate glacier ice and better predictions of glacier flow and sea-level rise.

Russia's Kremlin says it's watching Trump's pursuit of Greenland closely

The Kremlin said Thursday that it's keeping a close eye on President-elect Donald Trump's ongoing pursuit of Greenland.

Russia keeping close eye on Trump's claim to Greenland

The Kremlin reacts to the US president-elect's remarks saying the Arctic is in Russia's sphere of interest.

Million year-old bubbles could solve ice age mystery

What is probably the world's oldest ice, dating back 1.2m years ago, has been dug out from deep within Antarctica.

A major winter storm will bring snow to the South. Here are tips from winter experts

Southern states don't often deal with winter conditions, but New England does. New Hampshire especially has tips for how to prepare for a winter storm.

A topographically controlled tipping point for complete Greenland ice sheet melt

A topographically controlled tipping point for complete Greenland ice sheet melt Michele Petrini, Meike D. W. Scherrenberg, Laura Muntjewerf, Miren Vizcaino, Raymond Sellevold, Gunter R. Leguy, William H. Lipscomb, and Heiko Goelzer The Cryosphere, 19, 63–81, https://doi.org/10.5194/tc-19-63-2025, 2025 Anthropogenic warming is causing accelerated Greenland ice sheet melt. Here, we use a computer model to understand how prolonged warming and ice melt could threaten ice sheet stability. We find a threshold beyond which Greenland will lose more than 80 % of its ice over several thousand years, due to the interaction of surface and solid-Earth processes. Nearly complete Greenland ice sheet melt occurs when the ice margin disconnects from a region of high elevation in western Greenland.

Ros Atkins on...Trump's threats to Greenland

The BBC's Analysis Editor Ros Atkins takes a look at why President-elect Donald Trump is talking about annexing Greenland.

Where is Greenland and why does Trump want it?

Though the president-elect's rhetoric is unusual, for over a century a succession of US presidents have tried to gain control of Greenland.

Machine learning of Antarctic firn density by combining radiometer and scatterometer remote-sensing data

Machine learning of Antarctic firn density by combining radiometer and scatterometer remote-sensing data Weiran Li, Sanne B. M. Veldhuijsen, and Stef Lhermitte The Cryosphere, 19, 37–61, https://doi.org/10.5194/tc-19-37-2025, 2025 This study used a machine learning approach to estimate the densities over the Antarctic Ice Sheet, particularly in the areas where the snow is usually dry. The motivation is to establish a link between satellite parameters to snow densities, as measurements are difficult for people to take on site. It provides valuable insights into the complexities of the relationship between satellite parameters and firn density and provides potential for further studies.

European Union won't allow attacks on borders, French minister says after Trump's Greenland comments

In an interview on Wednesday, Jean-Noël Barrot addressed the U.S. President-elect's interest in Greenland.

Europe will not allow attacks, says France, after Trump Greenland threat

The intervention comes after Trump reiterated his desire to acquire the autonomous Danish territory.

Why Trump's pursuit of Greenland could be cheered on by Russia

President-elect Donald Trump's ongoing pursuit of Greenland may have raised the hackles of Denmark, but his territorial ambitions might find support in Russia.

A quasi-one-dimensional ice mélange flow model based on continuum descriptions of granular materials

A quasi-one-dimensional ice mélange flow model based on continuum descriptions of granular materials Jason M. Amundson, Alexander A. Robel, Justin C. Burton, and Kavinda Nissanka The Cryosphere, 19, 19–35, https://doi.org/10.5194/tc-19-19-2025, 2025 Some fjords contain dense packs of icebergs referred to as ice mélange. Ice mélange can affect the stability of marine-terminating glaciers by resisting the calving of new icebergs and by modifying fjord currents and water properties. We have developed the first numerical model of ice mélange that captures its granular nature and that is suitable for long-timescale simulations. The model is capable of explaining why some glaciers are more strongly influenced by ice mélange than others.

How Canada's immigration debate soured - and helped seal Trudeau's fate

Immigration has long been a polarising issue in the West but Canada mostly avoided it - until now

Proximity ferroelectricity in wurtzite heterostructures

Nature, Published online: 08 January 2025; doi:10.1038/s41586-024-08295-y

New research reveals groundwater pathways across continent

Researchers have created a simulation that maps underground water on a continental scale. The result of three years' work studying groundwater from coast to coast, the findings plot the unseen path that each raindrop or melted snowflake takes before reemerging in freshwater streams, following water from land surface to depths far below and back up again, emerging up to 100 miles away, after spending from 10 to 100,000 years underground.

Trump won't rule out using U.S. military to control Panama Canal or Greenland

President-elect Donald Trump has repeatedly said the U.S. should control the Panama Canal and Greenland, and has also expressed a desire to make Canada a state.

Trump threatens 'very high' tariffs on Denmark over Greenland

In a rambling news conference, the president-elect also repeated the idea of the US taking over Canada and the Panama Canal.

New glacier thickness and bed topography maps for Svalbard

New glacier thickness and bed topography maps for Svalbard Ward van Pelt and Thomas Frank The Cryosphere, 19, 1–17, https://doi.org/10.5194/tc-19-1-2025, 2025 Accurate information on the ice thickness of Svalbard's glaciers is important for assessing the contribution to sea level rise in a present and a future climate. However, direct observations of the glacier bed are scarce. Here, we use an inverse approach and high-resolution surface observations to infer basal conditions. We present and analyse the new bed and thickness maps, quantify the ice volume (6800 km3), and compare these against radar data and previous studies.

The National Zoo's giant pandas make the most of DC's snow

The two giant pandas were seen on camera playing around in the snowfall that blanketed much of the Midwest and mid-Atlantic on Monday.

Lead pollution likely caused widespread IQ declines in ancient Rome, new study finds

Lead exposure is responsible for a range of human health impacts, with even relatively low levels impacting the cognitive development of children. Scientists have previously used atmospheric pollution records preserved in Arctic ice cores to identify periods of lead pollution throughout the Roman Empire, and now new research expands on this finding to identify how this pollution may have affected the European population.

Trump Jr to visit Greenland after father repeats desire for US ownership

The president-elect says US control of Greenland is an "absolute necessity".

Five dead as huge winter storm grips swathe of US

Seven US states declared emergencies owing to the polar vortex of icy air that usually circles the North Pole.

Floods linked to rise in US deaths from several major causes

Over the last 20 years, large floods were associated with up to 24.9 percent higher death rates from major mortality causes in the U.S. compared to normal conditions. A new study demonstrates the sweeping and hidden effects of floods --including floods unrelated to hurricanes, such as those due to heavy rain, snowmelt, or ice jams.

Marked decrease in Arctic pressure ridges

In the Arctic, the old, multiyear ice is increasingly melting, dramatically reducing the frequency and size of pressure ridges. These ridges are created when ice floes press against each other and become stacked, and are a characteristic feature of Arctic sea ice, an obstacle for shipping, but also an essential component of the ecosystem. In a recently released study scientists report on this trend and analyze observational data from three decades of aerial surveys.

Ringing in the new year with a warm Arctic

Newly discovered 'kiss and capture' mechanism explains the formation of Pluto and its largest moon

Billions of years ago, in the frigid outer reaches of our solar system, two icy worlds collided. Rather than destroying each other in a cosmic catastrophe, they spun together like a celestial snowman, finally separating while remaining forever linked in orbit. This is how Pluto and its largest moon, Charon, originated, according to a University of Arizona study that challenges decades of scientific assumptions.

What to know about winter storm hitting North America

The extreme weather is being caused by the polar vortex, an area of cold air that circulates around the Arctic.

Trump's eyeing Greenland - but other Arctic investment is frozen

While Trump eyes Greenland, Norway and Russia have put the brakes on their polar region investments.

Smoother sailing for Arctic ice

Nature Climate Change, Published online: 06 January 2025; doi:10.1038/s41558-024-02225-6

Climate change and terrigenous inputs decrease the efficiency of the future Arctic Ocean’s biological carbon pump

Nature Climate Change, Published online: 06 January 2025; doi:10.1038/s41558-024-02233-6

The changing nature of future Arctic marine heatwaves and its potential impacts on the ecosystem

Nature Climate Change, Published online: 06 January 2025; doi:10.1038/s41558-024-02224-7

Smoother sea ice with fewer pressure ridges in a more dynamic Arctic

Nature Climate Change, Published online: 06 January 2025; doi:10.1038/s41558-024-02199-5

Watch: Snow blankets parts of New York and Nebraska

Parts of the US have been covered in snow as a severe winter storm sweeps the country.

Chilean president makes historic trip to South Pole

Gabriel Boric is the first leader in the Americas to visit the South Pole, stressing Chile's "Antarctic mission".

The world record for "largest snowflake" is 15 inches. Is that possible?

Snowflakes. These intricate, whimsical crystals are a staple of magical wintry scenes, but how big can they really get? Well, according to the Guinness World Record keepers, the "largest snowflake" ever recorded was a whopping 15 inches in diameter. It was spotted near Missoula, Montana in 1887. But Kenneth Libbrecht, a physicist at Caltech, has long been skeptical of that record. So he set out to find what makes a snowflake a snowflake and whether that 1887 record is scientifically possible. You can read more about what he discovered here. (encore)Want to share the snowflakes you've spotted this winter? Email us a photo at shortwave@npr.org.

Limited decrease of Southern Ocean sulfur productivity across the penultimate termination

Nature Geoscience, Published online: 03 January 2025; doi:10.1038/s41561-024-01619-7

Substantial and overlooked greenhouse gas emissions from deep Arctic lake sediment

Nature Geoscience, Published online: 03 January 2025; doi:10.1038/s41561-024-01614-y

Increased wildfire activity may be a feature of past periods of abrupt climate change

A new study investigating ancient methane trapped in Antarctic ice suggests that global increases in wildfire activity likely occurred during periods of abrupt climate change throughout the last Ice Age.

A pulsar-like polarization angle swing from a nearby fast radio burst

Nature, Published online: 01 January 2025; doi:10.1038/s41586-024-08184-4

Diversity and biogeography of the bacterial microbiome in glacier-fed streams

Nature, Published online: 01 January 2025; doi:10.1038/s41586-024-08313-z

What the Mysterious Bloop Taught Us About Antarctica

Was the infamous “bloop” a sea monster? Learn why this noise was a good reminder that we should keep an eye on the South Pole.

In a Political Year, Some Deaths Spoke to the Struggles for Democracy

Among the notable figures who died in a sometimes polarizing 2024, many championed justice, equal rights and political freedom.

How five top CEOs described the AI boom in 2024

CEOs from Nvidia, CrowdStrike, Snowflake, AMD and Generac on how the new technology is affecting business and the broader tech sector.

In a Political Year, Some Deaths Spoke to the Struggles for Democracy

Among the notable figures who died in a sometimes polarizing 2024, many championed justice, equal rights and political freedom.

How a fox skull shape conquers the snow

Research explains how foxes hunting mice can plunge down into the snow at high speeds without injuring their poor little snouts.

The Magnetic North Pole Is Drifting Across the Arctic Toward Siberia

Learn why the magnetic north pole has been moving away from Canada and toward Siberia over the past century, accelerating in recent decades.

Weatherwatch: Chinese avalanche photos reveal electrical phenomenon

Star-gazer’s long-exposure shots unexpectedly capture mysterious blue light of triboluminescence

On 27 October, photographer Shengyu Li set up his camera on a long exposure to record stars in the night sky near a mountain in Sichuan, China. As he waited, suddenly an unstable block of ice broke free from a glacier near the peak of the mountain and set off an avalanche. Looking at his photographs afterwards revealed mysterious blue flashes given off from the avalanche, when the ice crashing down smashed into rocks and the friction gave off the flashes of blue light. It was a phenomenon called triboluminescence, which occurs when certain materials are mechanically stressed from fracturing, scratching or rubbing.

This strange effect was widely seen in the 1790s, when sugar began to be produced with more refined sugar crystals. These crystals were made into large cones which could be nipped into chunks as needed. If the nipping was done in dim light, it gave off tiny bursts of light. Something similar is caused by rubbing the sides of quartz crystals together or even when pulling sticky tape from a roll.

Snowboarder's death in Swiss Alps avalanche is a reminder that even pros face risk

The death of an Olympic snowboarding athlete is a reminder that even the most skilled and experienced athletes are not immune to the threat of avalanches, and that knowledge is key to staying safe.

Image: NASA's Terra satellite captures 2015 eclipse shadow

During the morning of March 20, 2015, a total solar eclipse was visible from parts of Europe, and a partial solar eclipse from northern Africa and northern Asia. NASA's Terra satellite passed over the Arctic Ocean on March 20 at 10:45 UTC (6:45 a.m. EDT) and captured the eclipse's shadow over the clouds in the Arctic Ocean.

Greenland and the Panama Canal aren't for sale. Why is Trump threatening to take them?

Trump's promises to use America's strength to its advantage helped propel him twice to the White House.

Penguins and iceberg-watching: Marking Christmas in Antarctica

Staff working out in the wilds of Antarctica share their Christmas Day plans.

Denmark boosts Greenland defence after Trump repeats desire for US control

The huge package is announced after the president-elect said US ownership of Greenland was a "necessity".

Skiing, wool baubles, ice-cream: how Antarctic scientists celebrate Christmas

From the Flask glacier to King George Island, intrepid researchers expect good cheer, snow and penguins

Many of us will not get a white Christmas this year, but a group of scientists are guaranteed one while carrying out research on the Antarctic peninsula.

While ice and good cheer are expected, their yuletide activities will be very different from those back home. Dr Kate Winter, of Northumbria University, and colleagues will be deploying instruments on Flask glacier to study the way that meltwater affects how quickly glaciers flow into the ocean.

Kids can talk to Santa through Christmas Eve thanks to shortwave radio

On Christmas Eve, scientists at field stations across Antarctica sing carols to one another...via shortwave. On today's episode, the Short Wave podcast explores shortwave radio. We speak with space physicist and electrical engineer Nathaniel Frissell about this Antarctic Christmas Carol tradition and his use of shortwave radio for community science.Read more about Santa Net, which connects children (known in the shortwave radio community as "little harmonics") with Santa.Want more tech stories? Let us know by emailing shortwave@npr.org!Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave.

Football stadium-sized balloons launch in Antarctica for science experiments

Scientists with NASA are launching enormous balloons, the size of a football stadium, from the Antarctic ice. They're carrying experiments on dark matter and other mysteries.

'World's best-preserved mammoth' found in Siberia – video

Researchers in Russia have unveiled the near intact carcass of a juvenile female mammoth, whose remarkably well-preserved remains were discovered in thawing permafrost after more than 50,000 years. The creature was recovered from the Batagaika crater, a huge depression more than 80 metres (260 feet) deep which is widening as a result of climate change

• Baby mammoth in Russia is the ‘best-preserved’ ever found

Greenland again tells Trump it is not for sale

It comes after the US president-elect repeated comments he made in 2019 that he would like to purchase the territory.

Baby mammoth in Russia is the ‘best-preserved’ ever found

The 50,000-year-old female, nicknamed Yana, is one of only seven whole remains discovered in world

Russian scientists have displayed the remarkably well-preserved remains of a baby mammoth found in the permafrost-covered region of Yakutia in Siberia.

The 50,000-year-old female mammoth has been nicknamed Yana after the river in whose basin it was discovered this summer. Experts say it is the best-preserved mammoth carcass in the world and is one of only seven whole remains ever found.

I interviewed 70 parents who raised highly successful adults: 4 things they wish they had known

"Raising an Entrepreneur" author Margot Machol Bisnow interviewed 70 parents whose children became successful adults. Here's what they wish they had known.

The joy of trivia: ‘We wrote our book together to intrigue each other’

After midlife burnout came a rediscovered curiosity for two friends and writers

It was the early 2000s, we were in our 20s and had both started as assistants at the same company. We bonded over excruciating induction sessions, where we had to reveal things like which cartoon character we most identified with (B: Danger Mouse; E: Marcie from Peanuts). We laughed a lot, but we also worked really hard – and pushed each other to do new things. Twenty years later, with six children between us as well as more senior jobs, we found ourselves bogged down by endless to-lists and the relentless pace of midlife. We realised we needed to rediscover and connect to the positives in the world around us. The answer lay in sparking each other’s curiosity.

Many studies have shown that having a curious mindset has real-life benefits, both for our bodies and our souls. Our brains have evolved to release dopamine when we discover new things, and dopamine boosts memory, creativity and forges new neural connections. Other research shows that having a driving sense of curiosity can break down barriers between people – particularly important in our increasingly polarised world – c uriosity helps us to build empathy, connectivity and respect for others.

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.