Abstract: Based on the ORAS5 reanalysis dataset, it is shown that the ocean heat content (OHC) in the Barents Sea exists significant seasonal cycle, interannual variability and increasing trend during 1979–2018. The air-sea heat flux dominates the seasonal cycle of OHC, while the interannual variability and long-term trend of OHC are mostly impacted by the oceanic heat transport of the Atlantic inflow. Both the temperature and transport can explain the interannual variability of the oceanic heat transport carried by the Atlantic inflow, however, the enhancement of the oceanic heat transport is almost determined by the increased inflow temperature. Besides, we found distinct differences in air-sea heat exchanges associated with sea ice conditions in the Barents Sea: The ocean surface heat loss reduced and the mixed layer depth became shallower in the open water while the ocean surface heat loss was enhanced and the mixed layer depth deepened in the sea ice covered area.

Key words: Barents Sea, ocean heat content, oceanic heat transport, air-sea heat flux