Ice masses such as Arctic sea ice, permafrost, and Alpine glaciers are shrinking as Earth’s temperature warms.
Arctic Sea Ice Has Been Declining
Sea ice is frozen seawater that floats on the ocean’s surface and provides a habitat for a variety of species. The average thickness of sea ice in the Arctic Ocean has declined substantially over the past half-century.
This NASA visualization shows yearly sea ice minimums observed by satellite since 1979. In 2012, sea ice in the Arctic reached its lowest extent on record.
Visualization from Lori Perkins at NASA/Goddard Space Flight Center Scientific Visualization Studio with data provided by Rob Gerston.
The Greenland Ice Sheet Has Been Shrinking
Ice sheets, which originate on land, are in decline in the Arctic. In Greenland, ice sheet melt has increased 30 percent over the past 30 years.
This animation depicts changes in Greenland’s ice sheet mass from 2003-2009. Cool colors indicate ice mass decreases. Beige indicates increases. Overall, ice mass is decreasing; most ice is lost from Greenland’s edges.
Visualization from Luthcke, et al., "Recent Changes of the Earth's Land Ice from GRACE," presented at 2009 Fall AGU, H13G-02 (693337), Dec. 14, 2009. Source
Alpine Glaciers Have Been Receding
Nearly all of the world’s glacier systems are shrinking, and in many cases their rate of ice loss has been accelerating. These photographs document the decline of two Alaskan glaciers:
Toboggan Glacier, Prince William Sound, Alaska
Plateau Glacier, Saint Elias Mountains, Alaska
The decrease in global glacier volume since 1960 is summarized in this graph:
From U.S. Global Change Research Program. Global Climate Change Impacts in the United States: 2009 Report. Source