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These articles provide answers to frequently asked questions related to Earth's frozen realms. Questions range from general background information and detailed science processes to the data gathered and archived at the National Snow and Ice Data Center (NSIDC) and its data management programs including NOAA@NSIDC, the NASA NSIDC Distributed Active Archive Center (DAAC), and the Exchange for Local Observations and Knowledge of the Arctic (ELOKA). If you have a question that is not answered here, please contact NSIDC User Services.
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The Arctic ice cover plays an important role in maintaining Earth’s temperature—the shiny white ice reflects light and heat that the ocean would otherwise absorb, keeping the Northern Hemisphere cool. The continued loss of Arctic sea ice will include
Despite year-to-year variability, Arctic sea ice has steadily dropped during all seasons since the start of the satellite record in 1979. However, the changes are especially pronounced around the time of the sea ice minimum in September, when sea ice
Unlike people, animals, news stories, and sitcoms, Arctic sea ice has not gotten older with time—it has gotten younger. Very little old ice, typically four years old or older, remains. During the 1980s, this old ice covered a substantial portion of
Satellites have continuously monitored sea ice since 1979. To gauge what Arctic sea ice was like before then, scientists use a combination of historical records and proxy measurements such as marine sediment cores. Taken together, these records
Guest post by Mark Serreze, NSIDC Director and Professor, Department of Geography, University of Colorado Boulder The polar vortex is the region of the atmosphere that contains the hemisphere’s cold air, rotating from west to east. In the Northern
Permafrost, also known as frozen ground, is soil that remains at or below 0°C (32°F) for at least two years. When it thaws, permafrost contributes to global warming by releasing greenhouse gases into the atmosphere. A breakdown of decomposition In