Exploring methane detection with Sentinel-2 data: capabilities for monitoring landfill emissions

Abstract

Methane is an extremely potent greenhouse gas, as it is about 80 times more effective at trapping heat than carbon dioxide. To mitigate global warming and the related consequences, reducing our emissions of methane is crucial. Therefore, being able to detect unknown releases and monitor the effects of emission mitigation efforts is essential. A few satellites with methane monitoring as one of their main objectives have been launched and in recent years a range of studies have investigated the possibility of using other already existing satellites for the same purpose with promising results. About one fifth of the global annual methane releases originates from the waste sector, and monitoring of these areas can help mitigation efforts. Hence, this study centers around a one-year monitoring of a landfill in New Orleans, utilizing already published methods and the short-wave infrared bands (band 11 & band 12) of the freely available Sentinel-2 data. Landfills can act as both point sources and area sources, and remote sensing monitoring of such sites can help provide frequent emission data, as well as monitor areas that are inaccessible on foot.

The investigated methods show positive results over two different test sites with ideal background properties; however, we find that the inhomogeneous background and the operational-related changes in the surface of the landfill make it challenging to detect and monitor methane over the area.