The CALIPSO Night Validation Flights (CALIPSO-NVF) airborne deployment was conducted in August 2022 out of Bermuda. The goal was to conduct a series of nighttime underflights of the CALIPSO satellite with the NASA Langley High Spectral Resolution Lidar (HSRL-2).
Airborne measurements from the HSRL-2 instrument were essential for verifying the calibration accuracy of the CALIPSO lidar and for acquiring information on aerosol optical properties used for its aerosol profile retrievals. By flying under the CALIPSO ground track, HSRL-2 provided an independent measurement of lidar attenuated backscatter with a higher signal-to-noise ratio.
To obtain this important validation dataset, HSRL-2 was flown onboard NASA's B-200 King Air as CALIPSO passed within range of the aircraft. Researchers chose to fly over the western Atlantic Ocean to allow unobstructed, 45-minute flights along the satellite ground track. Four nighttime underflights were flown in cloud-free skies (on August 7, 10, 12, and 17), yielding ideal data for calibration validation. A fifth flight (August 18) targeted measurements beneath cirrus clouds to assess the accuracy of CALIPSO aerosol retrievals through high clouds at night, an important but previously unexplored validation target.
Total research flight time was 17.7 hours, sampling 2,200 km along the CALIPSO ground track.
Project DOI: 10.5067/SUBORBITAL/CALIPSO-NVF/DATA001
