Abstract
Libera is a next generation Earth-viewing scanning radiometer that will fly on the Joint Polar Satellite System-4 (JPSS-4), which is set to launch in 2027. Libera will provide continuity of Earth radiation budget measurements from the Clouds and Earth’s Radiant Energy System (CERES), enhance observing capabilities to support Earth radiation budget science goals and advance the development of self-contained observing systems. Libera measurements will be collected in four spectral channels: the shortwave channel [SW; (0.3 to 5) µm] to measure solar radiation reflected by the Earth, the longwave channel [LW; (5 to 50) µm] to measure the Earth thermal emission, split short-wave channel [SSW; (0.7 to 5) µm] to further quantify the shortwave energy deposition in the Earth system, and the total channel [TOT; (0.3 to 100+) µm] to measure the total radiation reflected and emitted by the Earth system.
Libera has undergone primary radiometric ground calibration at laser tie points from 0.260 µm to 15.5 µm in the Earth Radiance Facility (ERF) at LASP. Over 600 calibration data sets have been collected with the flight telescopes and detectors in ERF. ERF utilizes a tunable optical parametric amplifier (OPA) laser source to generate in-vacuum narrow band uniform radiance levels ≥ 100 W/m^2/sr for a large portion of the laser spectrum and ≥ 500 W/m^2/sr for much of the visible/NIR range. The absolute spectral response of the Libera science radiometers is set by comparison to the Planar Bolometric Radiometer for Radiance (PBR-R) standard reference detector.
This presentation will include a description of ERF, PBR-R, and the calibration methodology along with preliminary calibration results for the Libera science radiometers from the UV to MIR.
Libera Radiometric Ground Calibration in the Earth Radiance Facility (ERF)
Libera is a next generation Earth-viewing scanning radiometer that will fly on the Joint Polar Satellite System-4 (JPSS-4), which is set to launch in 2027. Libera will provide continuity of Earth radiation budget measurements from the Clouds and Earth’s Radiant Energy System (CERES), enhance observing capabilities to support Earth radiation budget science goals and advance the development of self-contained observing systems. Libera measurements will be collected in four spectral channels: the shortwave channel [SW; (0.3 to 5) µm] to measure solar radiation reflected by the Earth, the longwave channel [LW; (5 to 50) µm] to measure the Earth thermal emission, split short-wave channel [SSW; (0.7 to 5) µm] to further quantify the shortwave energy deposition in the Earth system, and the total channel [TOT; (0.3 to 100+) µm] to measure the total radiation reflected and emitted by the Earth system.
Libera has undergone primary radiometric ground calibration at laser tie points from 0.260 µm to 15.5 µm in the Earth Radiance Facility (ERF) at LASP. Over 600 calibration data sets have been collected with the flight telescopes and detectors in ERF. ERF utilizes a tunable optical parametric amplifier (OPA) laser source to generate in-vacuum narrow band uniform radiance levels ≥ 100 W/m^2/sr for a large portion of the laser spectrum and ≥ 500 W/m^2/sr for much of the visible/NIR range. The absolute spectral response of the Libera science radiometers is set by comparison to the Planar Bolometric Radiometer for Radiance (PBR-R) standard reference detector.
This presentation will include a description of ERF, PBR-R, and the calibration methodology along with preliminary calibration results for the Libera science radiometers from the UV to MIR.