Arctic Cyclone Activity and the Beaufort High

Abstract The Beaufort high (BH) and its accompanying anticyclonic winds drive the Arctic Ocean’s Gyre, major freshwater reservoir of Ocean. Gyre circulation capacity to accumulate or release rely on BH intensity. migration Nordic seas cyclones into has been hypothesized moderate strength BH. We explore this hypothesis by analyzing reanalysis sea level pressure fields characterize identify track north 60°N during 1948–2019. A cluster analysis cyclone trajectories reveals a western pathway (through interior) associated with relatively weak an eastern (along periphery) strong Furthermore, we construct activity indices (CAIs) in that take account multiple parameters (number, strength, duration). There are significant correlations between CAIs 1948–2019, anomalously related BH, vice versa. show how experienced regime shift toward increased first four decades analyzed (1948–88) most recent three (1989–2019). Over same two time periods, exhibits weakening. Increased weakening may be consistent expectations warming have implications for dynamics freshwater.