Cryosphere
![Overview of the Cryosphere and its larger components, from the UN Environment Programme Global Outlook for Ice and Snow.](/Images/godic/202501/07/Cryosphere_Fuller_Projection1205.png")
![This high resolution image, designed for the Fifth Assessment Report of the IPCC, shows the extent of the regions affected by components of the cryosphere around the world. Over land, continuous permafrost is shown in a dark pink while discontinuous permafrost is shown in a lighter shade of pink. Over much of the northern hemisphere's land area, a semi-transparent white veil depicts the regions that are affected by snowfall at least one day during the period 2000-2012. The bright green line along the southern border of this region shows the maximum snow extent while a black line across the North America, Europe and Asia shows the 50% snow extent line. Glaciers are shown as small golden dots in mountainous areas and in the far northern and southern latitudes. Over the water, ice shelves are shown around Antarctica along with sea ice surrounding the ice shelves. Sea ice is also shown at the North Pole. For both poles. the 30 year average sea ice extent is shown by a yellow outline. In addition, the ice sheets of Greenland and Antarctica are clearly visible.](/Images/godic/202501/07/lossless-page1-300px-Components_of_the_Cryosphere.tif1205.png")
The cryosphere (from the Greek κρύος kryos, "cold", "frost" or "ice" and σφαῖρα sphaira, "globe, ball") 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). Thus, there is a wide overlap with the hydrosphere. The cryosphere is an integral part of the global climate system with important linkages and feedbacks generated through its influence on surface energy and moisture fluxes, clouds, precipitation, hydrology, atmospheric and oceanic circulation. Through these feedback processes, the cryosphere plays a significant role in the global climate and in climate model response to global changes. The term deglaciation describes the retreat of cryospheric features. Cryology is the study of cryospheres.