Satellite ocean color assessment of air-sea fluxes of CO2 in a river-dominated coastal margin -: art. no. L01601

Quantification of the contributions of river-influenced margins to regional CO2 fluxes is difficult due to the high degree of spatial and temporal variability in these regions. We describe an algorithm for assessment of surface water partial pressure of CO2 (pCO(2)) from MODIS imagery in the northern Gulf of Mexico. Principal component analysis and multiple regression were used to relate surface pCO(2) to environmental variables (T, S, chlorophyll). Subsequent retrieval of corresponding products from MODIS-Aqua L1B data permitted the assessment of regional distributions of pCO(2). An area of low pCO(2) was evident in the vicinity of the Mississippi River delta, consistent with field observations. Regional surface air to sea fluxes of CO 2 were estimated as 2.0-4.2 mmol C m(-2) d(-1).