Figure 6
From: Evaluating methane inventories by isotopic analysis in the London region

Methane mole fractions (ppm) measured in central London on 20th March 2015 between 8 and 9 a.m. The map was generated using ArcMap 10.2. Base map source: Esri, DigitalGlobe, GeoEye, i-cubed, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community. British National Coordinate System shown.