The Polar Radiant Energy in the Far Infrared Experiment: A New Perspective on Polar Longwave Energy Exchanges

• Published in: Bulletin of the American Meteorological Society 2021-07, Vol.102 (7), p.E1431-E1449
• Main Authors: L’Ecuyer, Tristan S., Drouin, Brian J., Anheuser, James, Grames, Meredith, Henderson, David S., Huang, Xianglei, Kahn, Brian H., Kay, Jennifer E., Lim, Boon H., Mateling, Marian, Merrelli, Aronne, Miller, Nathaniel B., Padmanabhan, Sharmila, Peterson, Colten, Schlegel, Nicole-Jeanne, White, Mary L., Xie, Yan
• Format: Article
• Language: English
• Subjects: 21st century; Ambient temperature; Arctic circulation; Arctic sea ice; Atmosphere; Atmospheric circulation; Atmospheric effects; Climate; Climate change; Climate variations; Cloud properties; Cubesat; Detectors; Earth; Emission measurements; Emissivity; Energy; Energy budget; Energy transfer; Far infrared radiation; Glaciation; Greenhouse effect; Heat exchange; Heat transmission; Heat transport; I.R. radiation; Ice sheets; Infrared emissions; Infrared radiation; Latitude; Miniaturization; Polar environments; Polar regions; Radiation; Sea ice; Seasonal variations; Seasonality; Spectrum analysis; Surface energy; Surface properties; Temporal variations; Thermal emission; Thermal energy; Water vapor; Water vapour; Wavelengths
• ISSN: 0003-0007; 1520-0477
• DOI: 10.1175/BAMS-D-20-0155.1

Earth’s climate is strongly influenced by energy deficits at the poles that emit more thermal energy than they receive from the sun. Energy exchanges between the surface and atmosphere influence the local environment while heat transport from lower latitudes drives midlatitude atmospheric and oceanic circulations. In the Arctic, in particular, local energy imbalances induce strong seasonality in surface–atmosphere heat exchanges and an acute sensitivity to forced climate variations. Despite these important local and global influences, the largest contributions to the polar atmospheric and surface energy budgets have not been fully characterized. The spectral variation of far-infrared radiation that makes up 60% of polar thermal emission has never been systematically measured impeding progress toward consensus in predicted rates of Arctic warming, sea ice decline, and ice sheet melt. Enabled by recent advances in sensor miniaturization and CubeSat technology, the Polar Radiant Energy in the Far Infrared Experiment (PREFIRE) mission will document, for the first time, the spectral, spatial, and temporal variations of polar far-infrared emission. Selected under NASA’s Earth Ventures Instrument (EVI) program, PREFIRE will utilize new lightweight, low-power, ambient temperature detectors capable of measuring at wavelengths up to 50 μm to quantify Earth’s far-infrared spectrum. Estimates of spectral surface emissivity, water vapor, cloud properties, and the atmospheric greenhouse effect derived from these measurements offer the potential to advance our understanding of the factors that modulate thermal fluxes in the cold, dry conditions characteristic of the polar regions.