Hydrology and Land Surface Studies
A projection of severe near-surface permafrost degradation during the 21st century
Article first published online: 17 DEC 2005
Copyright 2005 by the American Geophysical Union.
Geophysical Research Letters
Volume 32, Issue 24, December 2005
How to Cite
2005), A projection of severe near-surface permafrost degradation during the 21st century, Geophys. Res. Lett., 32, L24401, doi:10.1029/2005GL025080., and (
- Issue published online: 17 DEC 2005
- Article first published online: 17 DEC 2005
- Manuscript Accepted: 15 NOV 2005
- Manuscript Revised: 6 NOV 2005
- Manuscript Received: 31 OCT 2005
 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.