Optimizing irradiance estimates for coastal and inland water imaging spectroscopy

Next generation orbital imaging spectrometers, with advanced global remote sensing capabilities, propose to address outstanding ocean science questions related to coastal and inland water environments. These missions require highly accurate characterization of solar irradiance in the critical 380–600 nm spectral range. However, the irradiance in this spectral region is temporally variable and difficult to measure directly, leading to considerable variance between different models. Here we optimize an irradiance estimate using data from the NASA airborne Portable Remote Imaging Spectrometer (PRISM), leveraging spectrally smooth in-scene targets. We demonstrate improved retrievals for both PRISM and the Next Generation Airborne Visible Infrared Imaging Spectrometer.