Wednesday, February 24, 2010

Barents Sea: An Effective Ocean Cooler

The Barents Sea is a robust and effective ocean cooler. Despite its fairly shallow depth of 230 meters, it releases more energy to the atmosphere than any other sea around the Arctic.

A new study by four oceanographers in Bergen shows how the Barents Sea responds to variation of heat transport by the ocean. Results show that the northwards migration of the sea ice, and the larger open ocean areas in the south, can compensate for much of the increase in ocean heat transport since the mid 1990's.

The paper, published in Ocean Science, describes a new approach for understanding the Barents Sea. First, an overall heat budget had to be produced, including mean monthly ocean transport and atmospheric forcing. New estimates including the Norwegian Coastal Current makes the total transported heat to the Barents Sea about 70 TW. The researchers have divided the Barents Sea into a northern and southern area, and show that all of the heat is lost to the atmosphere in the south.

The heat is lost by the ocean in the southern Barents Sea through evaporation and sensible fluxes, as there is an approximate balance between the incoming solar, and the outgoing long wave, radiation. The northern Barents Sea receives little ocean heat transport, leading to early sea ice formation during winter.

No comments: