The mean FFP among studies that measured city-level CH4 emissions on the U.S. west coast is comparatively lower (48.4% ± 27.2%). FFPs measured by in Los Angeles are included in this estimate but are not shown in Figure because quantification was not performed. The mean FFP for Los Angeles (62.4% ± 15.9%) is substantially higher than the SFBA (13.5% ± 4.9%), which has a large landfill contribution (74%) to total CH4 emissions . The large standard deviation for Los Angeles is partly explained by the large FFP (89.0%) reported by , which is a large percentage compared to other studies. FFP estimates in most other Los Angeles-focused studies ranged from 58% to 62% . Landfills are estimated to account for most of the non-fossil CH4 emissions in Los Angeles .