A projection of severe near-surface permafrost degradation during the 21st century
Abstract
The current distribution and future projections of permafrost are examined in a fully coupled global climate model, the Community Climate System Model, version 3 (CCSM3) with explicit treatment of frozen soil processes. The spatial extent of simulated present-day permafrost in CCSM3 agrees well with observational estimates - an area, excluding ice sheets, of 10.5 million km2. By 2100, as little as 1.0 million km2 of near-surface permafrost remains. Freshwater discharge to the Arctic Ocean rises by 28% over the same period, largely due to increases in precipitation that outpace increases in evaporation, with about 15% of the rise directly attributable to melting ground ice. Such large changes in permafrost may provoke feedbacks such as activation of the soil carbon pool and a northward expansion of shrubs and forests.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- December 2005
- DOI:
- 10.1029/2005GL025080
- Bibcode:
- 2005GeoRL..3224401L
- Keywords:
-
- Cryosphere: Permafrost (0475);
- Atmospheric Processes: Climate change and variability (1616;
- 1635;
- 3309;
- 4215;
- 4513);
- Atmospheric Processes: Global climate models (1626;
- 4928);
- Planetary Sciences: Solid Surface Planets: Hydrology and fluvial processes;
- Geographic Location: Arctic region (0718;
- 4207)