The cryosphere is the part of the Earth‘s climate system that includes solid precipitation, snow, sea ice, lake and river ice, icebergs, glaciers and ice caps, ice sheets, ice shelves, permafrost, and seasonally frozen ground. The term “cryosphere” traces its origins to the Greek word ‘kryos’ for frost or ice cold.

The cryosphere extends globally, existing seasonally or perennially at most latitudes, not just in the Arctic, Antarctic, and mountain regions, and in approximately one hundred countries. Approximately 70% of the Earth’s freshwater exists as snow or ice.

Snow and ice data are required for weather and climate research and applications. As the cryosphere changes due to climate change, this has major impacts on society, on the availability of freshwater resources, agriculture, transportation, safety and security, hydropower production, recreation, increasing the risk of floods and droughts, and affecting the viability of ecosystems. 

Most people on Earth depend directly or indirectly on the cryosphere. For example, as all major rivers originate from mountains, the mountain cryosphere plays an important role in providing and regulating freshwater resources for around half of the world’s population, including for those living in lowland areas, such as the Ganges-Brahmaputra Delta. Furthermore, alterations and loss of critical snow and ice are increasing the risk of related disasters.

WMO has assumed a leading role in facilitating the access to accurate and timely information on cryosphere to support specific needs of its Members, to strengthen its ability to support ongoing development and delivery of weather, climate, and water services contributes to ensuring the sustainable development and well being of nations.


Northern Hemisphere Summer 2020 - Extreme events in the ice shelves and glaciers of the world

A record breaking summer in the Arctic

Temperatures in the Arctic are rising faster than the global average. Unique amplification processes and feedbacks, such as the rapid decline of sea ice significantly contribute to this warming. The effects vary in time and scale across the Arctic, and the consequences of a warming Arctic will be far-reaching across the northern hemisphere. Read more...