WHOI PO

Ken Zhao, Scripps & Oregon State University - What Drives Offshore Freshwater Flux from the Greenland Shelf?
Date Time Location
November 26th, 2024 3:05pm-4:05pm Clark 507
Title: What Drives Offshore Freshwater Flux from the Greenland Shelf?
Abstract: The Greenland coastal current transports freshwater from the Arctic and Greenland Ice Sheet, playing a critical role in dense water formation as it fluxes off the shelf. Observations from five summertime OSNAP (Overturning in the Subpolar North Atlantic Program) cruises reveal significant differences between the East and West Greenland coastal currents near Cape Farewell, Greenland’s southernmost point, indicating substantial freshwater flux off the shelf near this region.

Motivated by these observations and a 1/60° regional model, we use an idealized nonhydrostatic GPU ocean model to investigate how winds, bathymetry, and buoyancy regulate these fluxes. Sensitivity tests underscore the role of eddy kinetic energy in enhancing offshore transport, counteracting potential energy buildup under downwelling-favorable winds. The combination of wind stress and shelf depth transitions therefore makes Cape Farewell a particularly favorable location for offshore freshwater flux.

Our findings shed light on Greenland coastal current dynamics along the shelf and offer a framework for interpreting OSNAP observations, which are spatially under-resolved on the shelf. These results have significant implications for future freshwater fluxes and dense water formation under changing climate conditions.