Since 1978, he has worked at NASA Goddard Space Flight Center in Greenbelt, Maryland. During his career at NASA, he has conducted research on the couplings between ocean physics and biology and the marine carbon cycle using satellite ocean color data. He was a member of the CZCS reprocessing team in the late 1980s and has assumed a number of project management roles including the SeaWiFS calibration and validation manager, project scientist, and project manager, SIMBIOS project manager, and ocean team leader for MODIS, NPP/VIIRS, and the ACE mission formulation activity. He recently served as a member of the PACE mission science definition team. He was the original principle investigator for the PC-SEAPAK and SeaDAS software packages distributed to the ocean color research community.