Towards Modeling the Carbon Cycle of the Arctic Ocean

M. Manizza,  M. J. Follows, S. Dutkiewicz, C. N. Hill, and D. Menemenlis

We will describe a numerical model of the circulation and biogeochemistry of
the Arctic Ocean which we use to estimate, and elucidate controls on, regional
air-sea fluxes of CO2 in the 1990s.  The model is based on the Arctic sector
of an eddy-permitting ocean model (MITgcm) with physical forcing derived from
NCEP re-analysis products.  A coupled sea-ice model captures the seasonal and
interannual variations in of sea-ice cover. It is overlain by a simplified
ocean biogeochemistry model which explicitly represents the coupled cycles of
carbon, alkalinity, phosphorus.  Terrestrial sources of dissolved organic
carbon are imposed as riverine fluxes. We will present preliminary model
estimates of regional, seasonal and interannual air-sea CO2 fluxes for the
period 1992-2001, comparing modeled fields and fluxes where possible to
observations.  We will discuss the significance of riverine DOC for the
regional air-sea flux.