Fig. 1: Examples of urban- and facility-scale satellite observations of methane plumes.
From: Global satellite survey reveals uncertainty in landfill methane emissions
a–o, Examples of GHGSat facility-scale (b,d,f,g,h,j,k,m) and TROPOMI-detected urban-area (a,c,e,l) methane emission plumes for urban areas in Charlotte (USA, a,b), Bucharest (Romania, c,d), Hyderabad (India, e,f), Guadalajara (Mexico, g), Córdoba (Argentina, h), Hong Kong (China, j), Bangkok (Thailand, k) and Casablanca (Morocco, l,m). The spatio-temporal distributions of all GHGSat plume origins and Sentinel-2-detected surface activity (structural changes between visual Sentinel-2 images; Methods) for the Casablanca landfill are shown in n and o, respectively. Black crosses mark site locations, whereas white dots represent the GHGSat plume origins and thick black contours demarcate landfill site boundaries. White arrows (a–h, j–m) illustrate the wind direction sampled from the ERA5 reanalysis48, with the associated labels indicating the wind speed. Plumes overall follow the reanalysis wind direction, with some exceptions at low wind speeds. Background imagery relies on non-concurrent Sentinel-2 data (2022). Copernicus Sentinel-2 data in parts a–h,j–o are adapted from Google Earth Engine49,50. Scale bars, 50 km (a,c,e,l), 1 km (b,d,f,g,h,j,k,m,n,o).
