Lagrangian study of mesoscale circulation in the Alaskan Stream area and the eastern Bering Sea

The Alaskan Stream is the western boundary current in the subarctic North Pacific. The Alaskan Stream area is characterized by a significant temperature, salinity and density differences between the coastal and open-ocean waters and strong mesoscale dynamics. In this paper, we demonstrate the transport pathways of the Alaskan Stream Water in the eastern subarctic Pacific and its extension into the eastern Bering Sea from 1 October 1994 to 12 September 2016 with the help of altimetry-based Lagrangian maps. Mesoscale eddy activity along the boundary between the shelf and deep-basin in the Alaskan Stream region and the eastern Bering Sea is shown to be related to the wind stress curl in the northern North Pacific in winter. A significant correlation is found between the concentration of chlorophyll a in the Alaskan Stream area and eastern Bering Sea in August September and the wind stress curl in the northern North Pacific in November March. The mesoscale dynamics, forced by the wind stress curl in winter, may influence not only lower trophic-level organism biomass but also salmon abundance and catch in the study area.