In October and November 2020, scientists from the Institute of Atmospherics Physics (IPA) were targeting European emission sources of climate relevant trace species. The METHANE-To-Go-Europe campaign with the DLR Falcon 20 aircraft took place under strict COVID-19 safety regulations out of Oberpfaffenhofen. The group of scientists from the Department of Atmospheric Trace Species spent almost 50 hours in the air. The 14 science flights were mainly conducted in Italy and in the Balkan states of Croatia, Serbia and Bosnia-Herzegovina.
The observations focused on characterizing methane (CH4) emissions from natural gas extraction platforms in the Adriatic Sea (Picture 1). Methane is the second most important anthropogenic greenhouse gas after carbon dioxide (CO2) and currently contributes with 20-25% to the man-made greenhouse gas effect. CH4 is the main compound in natural gas and can be released during extraction due to production processes or leakages. The measurements in the Adria were an important preparation for the observation of methane emissions from oil and gas exploration facilities along the West African coast, which will be targeted in the framework of a UNEP (United Nations Environmental Programme) funded project also taking place with the DLR Falcon in summer 2021 (METHANE-To-Go Africa). Other anthropogenic and insufficiently constrained emitters are among others landfills, from which anaerobically produced methane escapes. Those were sampled around Naples, Italy (Picture 2).
The second scientific focus of the METHANE-To-Go Europe campaign were the strong emissions from coal-fired power plants on the Balkans (Picture 3). There are no EU rules controlling the atmospheric release of sulfur dioxide (SO2) in Serbia and Bosnia-Herzegovina, which is harmful to human health and an important aerosol precursor, influencing the local radiative budget.
The power plant SO2 exhaust plumes can be detected from space with the TROPOMI instrument on the ESA satellite Sentinel‑5P. Goal of the flights in the Balkan states is to improve these satellite observations using the high-precision in-situ observations from the Falcon aircraft. To our knowledge these are the first airborne observations of power plant emissions in this region, which were only possible through the support from local partners (University Union-Nikola Tesla, Serbia / University of Novi Sad, Serbia / PSRI Institute for Protection and Ecology, Bosnia-Herzegovina / Croatia Control).
Flight planning, especially the selection of target regions and flight patterns, was only possible with the help of accompanying forecast simulations with the MECO(n), HYSPLIT, and WRF model systems. The obtained dataset will improve our knowledge of long-lived greenhouse gases like methane and short-lived trace gases like sulfur dioxide. Additionally, the determined emission strengths will be an important input for model simulations of future climate change. Thus, this project helps to improve climate simulations and delivers findings for policy makers to reduce climate relevant emissions.
The METHANE-To-Go Europe campaign was conducted in collaboration with the DLR Remote Sensing Technology Institute (IMF) and DLR Flight Experiments (FX), who are in charge of TROPOMI satellite validation and the operation of the Falcon 20 aircraft, respectively.