global-cryosphere-watch

The Cryosphere

The cryosphere describes those portions of Earth's surface where water is in solid form. This includes snow, sea ice, glaciers, permafrost, etc.

Snow

Snow is precipitation in the form of ice crystals, originating in clouds where air temperatures are below freezing (0˚C, 32˚F), and generally where ground temperatures are less than 5˚C (41˚F).

Sea Ice

Sea ice is formed at the sea surface by the freezing of seawater. In contrast to icebergs, glaciers, ice sheets, and ice shelves, sea ice forms and melts entirely in the ocean.

GCW News

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Welcome to our new colleague, Rosie Bisset!

Welcome our new GCW colleague in the WMO Secretariat, Dr Rosie Bisset! She joined us on 1 February 2025 as a Scientific Officer in the newly established Cryospheric and Polar Infrastructure/Global Cryosphere Watch Section of the Infrastructure Department. Rosie was a postdoctoral researcher at the University of Northern British Columbia, where her main role involved working with airborne LiDAR datasets to quantify snow water equivalent in several forested watersheds within coastal British Columbia, Canada. Prior to this, she obtained her PhD at the University of Edinburgh where she focused on developing satellite and UAV remote sensing techniques for monitoring debris-covered glaciers in the Peruvian Andes and High Mountain Asia.

05 Mar 2025

2024 snow assessment is now available

Snow Assessment for Winter 2023-2024, Northern Hemisphere and Regional Aspects. Learn more.

05 Dec 2024

2023 snow assessment is now available

A snow assessment for 2023 is now available at https://globalcryospherewatch.org/assessments/snow/2023/.

26 Jan 2024

Early opening of Northwest Passage

On 29 August 2022, satellite data revealed the opening of the northern route of the Northwest Passage (NWP). The most recent year in which this route was open by this date was in 2011. Sea ice area in the northern NWP route was well below average but above the 2011 record low. The ice area in the southern route was also below normal. Read more at https://globalcryospherewatch.org/interesting/archive/nwp2022/.

09 Sep 2022