Interannual variability of Atlantic Water inflow and modification in the Barents Sea

Recent mid-latitude winter temperature is lower than that in the previous decade despite the global warming. Several studies suggested that the decline of sea ice in the Barents Sea induces the cold winter weather in the East Asian region through enhancement of the Siberian High. Since the winter ice-free region in the southern half of Barents Sea is caused by the warm Atlantic Water inflow through the Barents Sea Opening, the inflow and modification of Atlantic Water are largely related to the area of sea ice in Barents Sea. Therefore we focus on the mechanism of interannual variabilities of inflow and modification of Atlantic Water by using a realistically configured ice-ocean general circulation model for interpretation of mid-latitude climate change in the northern hemisphere. The simulated Atlantic Water routes in the Barents Sea are captured by bottom topography and similar to those suggested by observation. The cooling of Atlantic Water along its routes by the atmosphere is reproduced in our model. The modeled heat flux at the Barents Sea Opening (87 TW; 1 TW = 10 ¹² Watt) is consistent with observational estimates (73-103 TW). The enhancement of sea ice production along the northwestern coast of the Novaya Zemlya (coastal polynya), which is considered as a significant mechanism of Atlantic Water modification in the Barents Sea, is also consistent with estimates based on satellite observations. We will closely investigate the interannual variabilities of Atlantic Water inflow and modification.