A simulated distribution of Siberian river runoff in the Arctic Ocean

Abstract

Continental runoff is one of the major sources of the Arctic freshwater budget. As is generally known, it influences water column stratification and maintains Arctic halocline, which isolates the sea ice and the cold, fresh upper layer from the warmer, saltier Atlantic waters of the Arctic Ocean. An increase in river runoff was observed in recent years. It is suggested that this will have an impact on Arctic water mass transformations. However, few details are known regarding river freshwater export to the Central Arctic Basin. It is assumed that river water pathways in vast shelf seas and deep basins are closely related to atmospheric variability. In this study, we use three-dimensional coupled regional ocean-ice model simulations forced by atmospheric reanalysis data to investigate the change in Siberian rivers freshwater pathways in the Arctic Ocean due to the variability of atmospheric dynamics. A numerical experiment with an increasing runoff of the largest Siberian rivers is carried out. The consequences of adding freshwater to particular regions of the Arctic Ocean are analysed.