Characterizing vertical distributions of greenhouse gases from combined ground-based and airborne measurements to validate space missions: the MAGIC initiative.

Carbon dioxide (CO2) and methane (CH4) are the two main greenhouse gases (GHG)emitted by human activities. To better understand their concentration and vertical distributionin several key regions and to prepare future space missions dedicated to GHG, the MAGICinitiative has been put in place. MAGIC stands for: Monitoring of Atmospheric compositionand Greenhouse gases through multi-Instruments Campaigns. Gathering about 40 scientistsall together, the campaigns have two main goals: (i) to better understand the vertical exchangeof GHG along the atmospheric column, in connection with atmospheric transport, sourcesand sinks of the gases at the surface and in the atmosphere; (ii) to contribute to thepreparation and validation of space missions dedicated to the monitoring of greenhousegases. To address these objectives, various instruments are deployed on various platforms:aircraft, balloons, ground. They perform simultaneous observations of GHG concentration:direct in-situ observations at the surface or along the vertical, total and partial weightedcolumns. The MAGIC campaigns rely on SAFIRE Falcon20 measurements of gasconcentrations, temperature/humidity/wind/particles and GHG (CO2/CH4/CO/H2O)between 0 and 11 km altitude. The Falcon20 allows flying under any satellite tracksand making 0-11 km profiles at specific locations, such as ICOS/TCCON sites.They are complemented by balloon-borne instruments making 0-30 km profileswith AirCore atmospheric samplers and Amulse light laser-diode spectrometerslaunched at Aire-sur-l’Adour and Trainou, as well as by measurements of total columnswith portable Fourier Transform Spectrometers from the ground (EM27sun andCHRIS). The 2 first MAGIC campaigns have been organized in January and May 2018, the latter inthe framework of the CoMet (Carbon dioxide and Methane) campaign lead by DLR. Inparticular, on May 24th, a coordinated flight between SAFIRE/Falcon20 and DLR/HALO hasbeen performed to compare the column of CH4 measured by the lidar CHARM-F on boardHALO to the column computed from simultaneous Falcon20 and AirCore profiles.Altogether, 2 research aircrafts, 23 launches of meteorological balloons, four ICOSinstrumented sites and a dozen instruments for measuring the concentration of gases havebeen deployed for the 2018 campaign. This talk will present the results obtained during the MAGIC2018 campaign and highlightthe strong benefit of having simultaneous measurements by aircraft, balloons andground-based FTS to validate space missions. Plans for next MAGIC campaigns that will beorganized in July 2019 in France and in summer 2020 tentatively in Sweden will begiven. [ABSTRACT FROM AUTHOR]