Phytoplankton distribution and light absorption from space using differential optical absorption spectroscopy

Information on phytoplankton light absorption is necessary to derive accurate estimates of marine chl a concentration and primary production. Global satellite data on photosynthetically active radiation and chl a concentration are available from a suite of satellite imagers like CZCS, SeaWiFS, MODIS, MERIS and others, but spectral information of absorption by phytoplankton and other water constituents is still lacking. Therefore, we used Differential Optical Absorption Spectroscopy (DOAS) to study the retrieval of phytoplankton distribution and absorption with the satellite sensor Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). SCIAMACHY measures back scattered solar radiation in the UV-Vis-NIR spectral region with a high spectral resolution (0.2 to 1.5 nm). First results showing global phytoplankton distribution and the distinction of phytoplankton absorption signatures from different phytoplankton communities are presented.