Abstract: The PACE (Pre-Aerosol, Clouds and ocean Ecosystem) mission, anticipated for launch in the early 2020s, is designed to characterize oceanic and atmospheric properties. The primary instrument on--board will be a moderate resolution (approximately 1 km nadir) radiometer, called the Ocean Color Instrument (OCI). OCI will provide high spectral resolution (5 nm) from the UV to NIR (350 – 800 nm), with additional spectral bands in the NIR and SWIR. The OCI itself is an excellent instrument for atm…