NOx Production by Lightning as Inferred Using NO2 Slant Columns from GCAS during the GOES-R Validation Campaign

The purpose of the GOES-R Validation Campaign was to support post-launch validation of data products from the Advanced Baseline Imager (ABI) and Geostationary Lightning Mapper (GLM) aboard the GOES-16 satellite. As part of the campaign, the NASA ER-2 aircraft overflew thunderstorms in several regions of the U.S. during the March – May, 2017 time period. Instrumentation on the ER-2 included the GEO-CAPE Airborne Simulator (GCAS) which provided spectra in the UV/Vis range from which NO₂ slant columns were retrieved and the Fly’s Eye GLM Simulator (FEGS) that provided measurements through the cloud top of optical emissions from lightning for comparison with GLM observations. In this analysis, mean NO_x vertical columns derived from GCAS and accumulated GLM flashes are used to estimate mean NO_x production per flash for storms over the Lake Erie region (April 20), Huntsville, AL (April 22), eastern Colorado (May 8), Louisiana (May 12), and the western Atlantic near Kennedy Space Flight Center (May 14). Air mass factors (AMFs) necessary to convert slant columns to vertical columns are computed using the VLIDORT code, using the Lambertian surface assumption, cloud top height from the Cloud Physics Lidar onboard the ER-2, and NO₂ and NO_x vertical profiles attributed to lightning taken from NASA GMI-Replay model simulations performed with and without lightning NO_x emissions. The GOES-R Validation Campaign provided an opportunity to demonstrate the synergy of the future TEMPO observations with the GLM data