Arctic unlikely to experience sudden loss of sea ice during 21st century. 1 March 2011
Open water absorbs more solar radiation than ice, so reduced sea-ice cover enhances Arctic warming. This self-reinforcing mechanism has lead some to speculate that anomalously low summer-sea-ice seasons, such as occurred in 2007, could signal a sudden switch to ice-free summers in the region.
Steffen Tietsche and co-workers from the Max Planck Institute for Meteorology, Hamburg, Germany, constructed a series of model simulations to investigate how Arctic atmospheric and oceanic temperatures and circulation patterns might respond following an ice-free summer season (Tietsche, S., Notz, D., Jungclaus, J. H. & Marotzke, J. Recovery mechanisms of Arctic summer sea ice. Geophys. Res. Lett. 38, L02707 (2011).). As expected, ice-free conditions in summer heated the ocean as more solar radiation was absorbed at the surface. However, thin ice cover the following winter offered less insulation and allowed more heat to escape back to the atmosphere. These mechanisms lead to a consistent recovery of sea ice in just a few years.
The results imply that an irreversible decline in Arctic sea ice is unlikely this century.
For further details, read the article in Nature Climate Change: Research Highlights
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