The components of the Earth system that contain a substantial fraction of water in a frozen state, i.e. sea ice, glaciers, ice sheets.
|National Snow and Ice Data Center, 2018|
The cryosphere is those portions of Earth's surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps, ice sheets, and frozen ground (which includes permafrost).
|Global assessment (1st work programme), Asia-Pacific assessment|