What are the impacts of an ice-depleted Arctic Ocean?

Arctic sea ice extent dropped to record lows during the northern summers of 2007 and 2008—part of a longer-term decline in the summer extent of sea ice on the Arctic Ocean. The impacts have physical, biological, and socio-economic dimensions—and they arise on all scales from local to global and on timeframes from days to decades. For example, the impacts of an ice-free Arctic Ocean have the potential to be quick and global because the effects of changing surface conditions (warmer, darker, more moisture) can be efficiently redistributed by the atmosphere. Shipping routes such as the Northwest passage and Northern Sea Route may become reliably navigable each summer, with attendant economic and environmental benefits and/or costs. And coastal Arctic social-biological systems already face great change and uncertainty as a result of recent trends in sea ice extent. Prediction of sea ice extent is made difficult by incomplete knowledge of sea ice thickness. Furthermore, external factors such as the patterns and trends of ocean and atmospheric circulation are not fully understood but are critical for improving the reliability of predictions.

One comment

1. thomas.wagner@nasa.gov says:

   at

   Loss of Arctic sea ice cover will dramatically change our world. The decreased albedo will heat the Arctic ocean, which is a key point in the ocean circulation system where warm, fresh Pacific water is turned to cold, salty Atlantic water. In addition, this heat will be transferred to the adjacent land where it will melt the permafrost, potentially releasing potent greenhouse gases like methane and dramatically altering the landscape. Finally, projection of atmospheric circulation predict a range of impacts, including decreased precipitation over parts of North America.