Emissions and atmospheric distribution of methane in Scandinavia: Results and lessons learned from the MAGIC2021 international campaign

In August 2021, a large-scale international campaign called MAGIC2021 took place in Scandinavia, with the aim of improving our knowledge of natural and anthropogenic emissions of methane and evaluate the contribution of satellite missions to the study of these emissions in the circumpolar region. Lead by CNRS and CNES, the campaign gathered 70 scientists from 14 research teams. During two weeks, more than twenty instruments were deployed on 3 research aircrafts, several small and large stratospheric balloons, as well as on ground. They covered a large region extending from Abisko Lake (Sweden) to Sodenkylä (Finland) and combined in-situ (air samplers, CRDS analyzers) and remote sensing observation (lidars, spectrometers) of atmospheric concentration of methane. Here, we will present the main results derived from the unique dataset of vertical profiles (from the ground to the mid-stratosphere), weighted columns (from the ground or from aircrafts) and 2D coverage at several altitudes of emission hotspots gathered during the MAGIC2021 campaign. We will show preliminary evaluation of wetland emissions inventories. We will also bring evidence for the crucial need for a better understanding of the vertical distribution of methane concentration, especially in the stratosphere, and the need to consider long-scale horizontal transport (e.g. fire emissions) in order to benefit from methane column measurement from remote sensing when inferring surface fluxes. Finally, we will present some lessons learned from the campaign and introduce future plans for large scale campaigns in the Artic. Main funding for the MAGIC2021 campaign came from CNES, CNRS, ESA, EUMETSAT and DLR. The campaign is part of the general MAGIC (Monitoring of Atmospheric composition and Greenhouse gases through multi-Instruments Campaigns) initiative launched in 2018 (https://magic.aeris-data.fr).