PREFIRE (Polar Radiant Energy in the Far-InfraRed Experiment)

Our group leads the NASA Earth Venture-Instrument (EV-I) Polar Radiant Energy in the Far-InfraRed (PREFIRE) mission. In collaboration with the Jet Propulsion Laboratory, University of Michigan, University of Colorado, and Blue Canyon Technologies, PREFIRE provides the first systematic measurements of the Earth’s far infrared emission spectrum and utilizes them to understand thermal energy balance in polar regions. The far infrared, defined as wavelengths longer than 15 micrometers, accounts for more than 60% of the thermal emission at polar latitudes. PREFIRE measurements will enable new insights into the surface emissivity, atmospheric greenhouse effect, and their variability essential for quantitatively modeling the surface/atmosphere interactions and feedbacks at the root of rapid polar climate change. Planned for launch readiness in late 2022, two CubeSats in polar orbit, each carrying a thermal infrared spectrometer utilizing a thermopile detector array that operates at ambient temperature will measure spectral radiances from 5-54 microns with 0.84 micron spectral sampling. The instruments will quantify the spectral characteristics of the surface, atmospheric water vapor, and clouds and their variability from sub-daily to seasonal timescales across the varied polar regimes encountered over the operational lifetime of one year. In addition to providing the first climatology of far infrared emission at both poles, the dual spacecraft measurement capability enables sub-diurnal sampling that allows the far infrared signatures and impacts of rapid melting and freezing processes to be characterized. For more information, see the PREFIRE website PREFIRE website or a preprint of our paper in the Bulletin of the American Meteorological Society.