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During the Deep Convective Clouds and Chemistry (DC3) experiment in summer 2012, airborne measurements were performed in the anvil inflow/outflow of thunderstorms over the Central U.S. by three research aircraft. A general overview of Deutsches Zentrum fur Luft- und Raumfahrt (DLR)-Falcon in situ measurements (CO, O3, SO2, CH4, NO, NOx, and black carbon) is presented. In addition, a joint flight on 29 May 2012 in a convective line of isolated supercell storms over Oklahoma is described based on Falcon, National Science Foundation/National Center for Atmospheric Research Gulfstream-V (NSF/NCAR-GV), and NASA-DC8 trace species in situ and lidar measurements.

Lightning discharges are one of the main sources of atmospheric NOx, contributing about 10% of NOx emissions globally and playing an important role for the concentration of ozone and other chemical species in the upper troposphere. Lightning produces between 2-8 Tg N per year globally (100-400 mol NOx per flash). Reducing the uncertainty of the NOx production by lightning and understanding the factors that influence this production is still a challenge. The TROPOspheric Monitoring Instrument (TROPOMI) is orbiting the Earth from a near-polar, sun-synchronous orbit since October 2017. TROPOMI is equipped with four spectrometers that provide information about the chemical composition of the troposphere with unprecedented horizontal spatial resolutions of 3.5 x 7 km before 6 August 2019 and 3.5 x 5.5 km after that date. In this work, we combine the DLR-NO2 research product, the DLR cloud operational product and the TROPOMI v2.1_test NO2 product to estimate the production of NOx per flash (LNOx). The v2.1_test NO2 product contains more useful data pixels than the official offline v1.x data product, because of better treatment of saturation of the TROPOMI measurements (which occurs frequently over high bright clouds that are often linked with LNOx) and the use of an improved version of the FRESCO cloud algorithm. We for the first time ever use these chemical measurements from TROPOMI combined with lightning radio measurements provided by the EUropean Cooperation for LIghtning Detection (EUCLID) and the Earth Network Total Lightning Network (ENTLN), together with lightning optical measurements provided by the space-based Lightning Imaging Sensor (LIS) to estimate the Detection Effiency (DE) of EUCLID and ENTLN. In addition, we use the ECHAM5/MESSy Atmospheric Chemistry (EMAC) simulations to calculate the air mass factor employed to convert tropospheric slant column of measured NO2 to vertical column LNOx and the winds provided by reanalysis data to eliminate the influence of upwind storms in the estimation of the background NOx. Concentration. We focus our analysis on different remote regions, where the background concentration of NO is relatively low. In particular, we focus our analysis on 11 thunderstorm cases taking place near the Pyrenees, where intense thunderstorms are frequent and the DE of EUCLID and ENTLN is relatively high and homogeneous. According to our preliminary results from a single case using the DLR-NO2 research product, we get about 400 mol NOx per flash when we estimate the background using NOx from CARIBIC flights and about 200-600 mol per flash when we estimate the background using TROPOMI measurements from non-flashing pixels.