Project: Collaborative Research: Particulate Organic Carbon Export off the Antarctic Peninsula by Nonlinear Mesoscale Eddies and Wind Forcing

NSF Award Abstract:

The Southern Ocean accounts for a large fraction of the global ocean CO2 uptake. The Southern Ocean is also unique because it encircles the globe, providing pathways for deep, inter-basin exchange. Previous studies have shown that particulate organic carbon (POC; fixed organic matter) seasonally builds up around the productive Antarctic seas before moving off-shore. The project will serve as a step toward better quantifying the export of POC from around the Antarctic Peninsula and better understanding the larger Southern Ocean carbon cycle. The project will promote education by supporting graduate and undergraduate students. New data sets on offshore transport pathways and POC variability will be generated in a consistent and systematic manner, and will be available to the scientific community.

This proposal will examine the offshore export of particulate organic carbon (POC) off the Antarctic Peninsula, from areas of high accumulation near the coast to areas offshore. We hypothesize that both wind-driven surface Ekman transport and transport by nonlinear mesoscale eddies can make significant contributions to the offshore export of POC. Specifically, the project will (1) identify areas of enhanced accumulation of POC off the Antarctic Peninsula; (2) quantify spatial and temporal variability in offshore transport by nonlinear mesoscale eddies and by winds in a surface Ekman layer; and (3) compare the estimates of offshore transport to the POC distribution away from the coast to identify preferred transport pathways or hotspots for offshore export of coastal water and POC off the Peninsula. This study will utilize decade-long satellite observations of POC based on algorithms validated against in situ data, ocean vector winds, eddy kinematic and propagation characteristics based on altimeter data, and results from a high resolution eddy resolving ocean model coupled to a sea ice model. The study will focus on the Antarctic Peninsula during summer, when reduced cloud/sea ice cover when satellite data availability is high.