Ocean Surface Carbon Dioxide Fugacity and Flux From Space

The ocean as the source and sink of carbon dioxide is important to global warming and ecology. We estimate the ocean-atmosphere exchanges in carbon dioxide through turbulence parameterization, which requires the difference in fugacity of carbon dioxide between sea and air, and a transfer velocity. There have been many studies on the parameterization of the transfer velocity in term of wind speed, momentum flux, or surface roughness observed by space radar. Fugacity in air is believed to change much less than in sea. Only very sparse in situ measurements of the fugacity are available. Multivariate linear regressions have been established in the past to relate the fugacity in sea to parameters that could be measured from space, but these relations are only applicable in limited regions and in specific season. We will present our results of using one of the most advanced statistical techniques to develop a statistical model for estimation of fugacity in sea over global ocean and all seasons, with spacebased measurements of sea surface temperature, chlorophyll, ocean dynamic topography, and salinity climatology. The seasonal and interannual variations of the fugacity in sea and their geographical distribution will be discussed.