First Quantitative Assessment of Anthropogenic Methane Sources Investigated by the CHARM-F Lidar during the CoMet 2.0 Arctic Airborne Campaign

The CoMet 2.0 Arctic airborne greenhouse gas measurement campaign took place over Canada in Summer of 2022. For the campaign, the German research aircraft HALO has been equipped with various instruments for remote-sensing and in-situ measurements of CO₂ and CH₄ and flown over target areas with potential sources of greenhouse gases, either natural (wetlands, thawing permafrost, etc.) or anthropogenic (oil and gas drilling sites, oil-sand mining, open-pit coal mines, landfills as well as biomass-burning in forest fires). With the city of Edmonton, Alberta as campaign base, a variety of sources of methane released due to human activity and adding substantially to the Canadian anthropogenic CH₄ budget were conveniently within reach for our measurements.

This presentation focuses on a selection of anthropogenic sources of CH₄ in Canada as well as the Valdemingómez and Pinto landfill sites near Madrid, which were targeted during a test flight. We show first results of the evaluation of active remote-sensing measurements that were conducted with DLR's CHARM-F lidar system. By using the Integrated-Path Differential-Absorption (IPDA)-lidar technique, CHARM-F enables measurements of total column concentrations of methane and carbon dioxide along flight tracks. After further adding wind information from auxiliary measurements or models, emission fluxes from localized sources can be estimated. We will highlight the top emitters in terms of estimated emission rate of CH₄ (in the 10kt/year range). Those are likely the most promising candidates for mitigation attempts.