Changes in heat content of the upper ocean for two adjacent 1¿¿1¿ areas (56¿--57 ¿N, 164¿--166¿W) in the eastern Bering Sea were investigated with the data from three quasi-synoptic surveys in June, August, and September 1976. Data from current meters indicated that the net flow was very weak, and advection of heat was neglected. The mean local change of heat content for the two areas for the June--August period was 0.20 cal cm-2 min-1; during August--September the local change was 0.06 cal cm-2 min-1. Mean surface exchange for the two periods was estimated by recently evaluated empirical formulas (using data from satellite photographs and weather reports) to obtain values of 0.20 and 0.05 cal cm-2 min-1. The data also suggested that the gain of heat through horizontal diffusion was not more than 0.01 cal cm-2 min-1. Thus for both periods there was excellent agreement between the local change of heat and the net surface exchange. It appears that net radiation is typically the dominant heat flux affecting much of the eastern Bering Sea in summer, although in early fall, evaporation starts to assume importance. This region is quite unusual in that heat advection and diffusion have little effect on the heat balance. Lack of motion allows the effects of various physical processes to be examined. |