Estimating and Modeling Air-sea Gas Fluxes in the Southern Ocean

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

This project is a study of the mechanisms controlling the air-sea flux of soluble gases - in particular chlorofluorocarbons (CFC's), carbon dioxide, and oxygen - in the Antarctic Circumpolar Current and the Southern Ocean. There are three objectives to the study: (1) a better understanding of the influence of mesoscale oceanic processes on tracer transport, and how to represent those processes in coarse resolution models; (2) the development of an innovative diagnostic approach to evaluating air-sea gas fluxes rooted in our understanding of the relationship between air-sea fluxes, ocean transports and biogeochemical transformations, and (3) testing this approach against explicit models of southern ocean biogeochemical cycles and apply it to observations to yield independent estimates air-sea carbon and oxygen flux. An existing global model will be used as a testbed. This model currently represents key biogeochemical processes with idealized parameterizations, however these are sufficient for an initial test of the basic assumptions of this diagnostic approach. The continued development of the global biogeochemical model will occur in parallel with this diagnostic work. This approach has great potential practical utility in supplementing current methods of estimating air-sea gas fluxes in the Antarctic Circumpolar Current. It will provide an explicit description of the connections between physical and biogeochemical processes, and will significantly improve the prognostic capabilities of such models in general.