Anticipated changes in the Nordic seas marine climate

Abstract

Possible future changes in the Nordic Seas marine climate are here discussed. The wide range of climate models used in the Intergovernmental Panel on Climate Change predict a global mean temperature increase between 1- 6ºC by the end of this century, with the estimates using the intermediate IPCC B2 scenario being in the range 1.9-3.4ºC. For climate models forced by a 1percent per year CO2 increase only, the so-called CMIP2 integrations, the increase in temperatures is close to 2ºC after CO2 doubling. For the Arctic region, the warming will probably be twice as high. A result is a rapid decline in the sea ice extent simulated by most models. Changes in the Nordic Seas region have been analysed in a CMIP2-integration with the Bergen Climate Model. In this model there is a trend towards more westerly winds, and by 2080 the entire Barents Sea is ice-free for all months of the year, and the Arctic Ocean ice-free during the summer months. There is a 1-2ºC warming of the Nordic Seas and Barents Sea, and a slight increase in the salinity. The Arctic Ocean is freshened, probably due to more ice melting and river runoff from the Eurasian continent. There is no indication of a reduction of the deepwater formation in the Nordic Seas.