The Polar Radiant Energy in the Far-Infrared Experiment (PREFIRE), Broadband Thermal Spectrometry for Small Satellite Platforms

For more than a decade the remote sensing community has called for longwave spectral measurements of the Earth system to facilitate closure of the radiation budget. In an effort to address the largest gaps NASA has supported development and implementation of the Polar Radiant Energy in the Far-Infrared Experiment (PREFIRE) which realizes two miniaturized thermal infrared spectrometers (TIRS) on each of two polar orbiting small-satellites with different ascending node crossing times. The spectral radiances measured by the PREFIRE-TIRS instruments are utilized to extract cloud presence, atmospheric state, surface properties, and the associated top-of-atmosphere spectral fluxes at a variety of polar conditions. This paper describes the major system and algorithm components and an overview of the geophysical data measurements. PREFIRE data will be used to inform and improve ice-sheet and coupled-earth system models to better predict the future state of the Earth's poles.