The reduction of sea-ice in the Arctic has gone faster than predicted during the last years. Little is known about the response times of species to climate change. For example, the rapid disappearance of sea ice may not allow for adaptive change by many arctic specialists and may possibly result in the disappearance of ice-dependent species. In areas of reduced sea-ice cover, primary production is very likely to increase, which in turn is likely to increase zooplankton and possibly fish production. Increased cloud cover is likely to have the opposite effect on primary production in areas that are currently ice free. A reduction in sea-ice extent is very likely to decrease the natural habitat for polar bears, ringed seals, and other ice-dependent species, which is very likely to lead to reductions in the survival of these species. However, increased areas and periods of open water are likely to be favourable for some whale species and the distribution of these species is very likely to move northward.

Reduced periods of land-fast ice may increase rates of coastal erosion, while unpredictable changes in land-fast and near-shore sea ice present new risks to native hunters. At present there seems to be little predictability in trends in sea ice cover in either summer or winter. Many factors (atmospheric circulation, ice-ocean albedo feedback, low cloud cover, ocean circulation, greenhouse gases) control sea ice and these are neither well-documented nor well-represented in models. Even so, the sea-ice community undertook a “sea ice outlook” project in summer 2008, perhaps the beginnings of a seasonal to interannual ice forecasting service.

Presentations on all of these topics are welcome in this session.

Session chairs

Koji Shimada 
Ignatius Rigor  
Lawson W. Brigham