A new Copernicus Atmosphere Monitoring Service for methane emissions at facility scale using atmospheric Copernicus Contributing Missions data.

The mitigation of methane emissions is one of the prime targets of global climate policy due to methane’s large contribution to global warming. Satellite instruments have proven to be very effective in mapping and tracking methane super-emitters. There are several new Copernicus Contributing Missions (CCMs) that are able to provide high resolution (~ 25m) methane abundance data that enables detection of emissions from individual facilities. We introduce a new Copernicus Atmosphere Monitoring Service (CAMS) service where we will use these CCMs to pinpoint individual methane sources all around the world to provide insights on emissions in support of mitigation efforts. The service will start with GHGSat data and aims to incorporate GEISAT and GESat data later. We will obtain observations over hundreds of methane hot spots and sites of interest around the world in support of climate policy. We process the satellite data starting from the methane abundance data provided by the CCMs using the SRON-developed HyperGas package. The data are standardized and potential methane plumes in the abundance field are automatically masked. Multiple expert operators then determine and agree on which masked features are true methane plumes. The automatically generated masks are then used for emission rate estimation using the integrated mass enhancement (IME) method. This methodology is calibrated using instrument-specific synthetic observations and will be evaluated using observations of controlled releases. Our semi-supervised approach allows for a consistent quantification of plumes over the full range of observations. Our processing is done independently from the analysis done by the CCMs themselves and thus serves as an evaluation. We also compare our results with bottom-up emission estimates such as included in the “TNO Emission Atlas”.  This way, our work can provide a crucial link between satellite methane observations and facility level bottom-up inventories.  We present our approach in consistently handling this large volume of data as well as initial results and interesting cases.