Satellite based productivity models across the Kuroshio extension

Abstract

[author abstract] As anthropogenic perturbations to the Earth’s climate have continued to become more severe, it has become increasingly necessary to understand the processes that control atmospheric CO2. One such process is the uptake and conversion of CO2 into organic material by phytoplankton. Their excess productivity can lead to an export of carbon out of the surface ocean which can be stored in ocean sediments. In this study, I compare two satellite based productivity models, the Vertically Generalized Production Model (VGPM) and the Carbon-based Production Model (CbPM) in the Kuroshio extension region of the Pacific. I found an unusually high variance between the two model’s NPP estimates. VGPM was as much as six times greater at 32° N while the opposite was true at 24° N, where CbPM estimated NPP to be more than double that of VGPM. These unusually large differences in the models estimates may be the result of the large nitrate gradient that exists are 30°N in the region.