Hyperspectral CoSMIR-H Aircraft Instrument and the WH2yMSIE Campaign

The NASA Planetary Boundary Layer (PBL) Incubation Study Team Report lists hyperspectral microwave (HMW) sensors as one of the “essential components” of a future global PBL observing system. HMW sensors will provide profiles of the PBL thermodynamic (temperature and water vapor) structure in synergy with passive infrared sounders and to complement active measurements (e.g., lidar and radar).

While many simulation studies have been performed showing the benefit of HMW observations, measurements are needed to demonstrate the efficacy of HMW retrievals. Under the Decadal Survey Incubation (DSI) program, NASA’s Goddard Space Flight Center (GSFC) developed an airborne HMW sensor by modifying the existing Conical Scanning Millimeter-wave Imaging Radiometer (CoSMIR) receivers with digital spectrometers. The new CoSMIR-Hyperspectral (CoSMIR-H) has 4-MHz spectral resolution spanning a range of 8 GHz between 50.0 and 58.0 GHz near the 60-GHz oxygen absorption band and a range of 16 GHz between 175.3 and 191.3 GHz centered on the 183.31 GHz water vapor absorption line. The fine spectral resolution can be averaged to match the bandwidth of current spaceborne sounders for inter-comparison of measurements and to validate improvement in vertical resolution of retrievals.

CoSMIR-H successfully flew for the first time in two separate campaigns in 2024 and collected approximately 60 hours of observations. Flights were focused on clear-sky conditions over both ocean and land to provide easier validation for HMW retrievals. This presentation will give an overview of the CoSMIR-H instrument and showcase observations from the Oct-Nov 2024 WH2yMSIE (Westcoast and Heartland Hyperspectral Microwave Sensor Intensive Experiment) campaign.