the 22nd Pacific−Asian Marginal Seas meeting (PAMS)

Pacific Water, which carries heat, freshwater, and nutrients from the Pacific Ocean, flows into the Arctic through the Chukchi Sea. Understanding its pathways is crucial for predicting Arctic change. This study investigates the export of Pacific Water from the Chukchi Sea shelf using a pan-Arctic sea ice-ocean model and a set of sensitivity experiments. An eight-year simulation (2013-2020) identifies a direct export across the wide shelf break west of Barrow Canyon, where the off-shelf flux (0.48 Sv) rivals the transport through the canyon itself (0.39 Sv). This western export is sustained by a shelf-wide transverse transport (0.52 Sv) that extends from the Alaskan coast to the western Chukchi Sea, nearly perpendicular to the main, topography-steered currents. This transverse flux is driven by surface and bottom stresses, and transforms into a geostrophic-dominant flux upon crossing the shelf break. Northeasterly winds act as the primary surface driver, although sea ice moderates wind forcing through its internal resistance. Notably, in calm wind conditions, sea ice can directly drive the transverse flux in a manner analogous to bottom drag. Our analysis highlights the role of nonlocal forcing and internal dynamical adjustment in modulating the export of Pacific Water.

Pacific Water,Chukchi Sea,Winds,Sea Ice