Quantifying the Anthropogenic Methane Emission from Large Local Sources

Abstract

Methane is a potent greenhouse gas. The aim of the project is to quantify anthropogenic emissions of methane from large local sources, such as cities and industrial facilities using satellite data. Of scientific interest is the comparison of methane emissions estimated using top down (satellite) and bottom up (statistical inventories) approaches. We make use of satellite data from SCIAMACHY. In an earlier master research project, a new local methane emission hotspot is found in South Shānxī Province, China with the satellite data, which is not shown in EDGAR version 4.2, but added in the latest EDGAR draft version 4.3.2. Together with a well validated methane hotspot in Four Corners, USA, the methane emissions of these two hotspots are studied in this research. China has complicated local anthropogenic methane emission sources, but without a precise measurement inventory. In this research, based on TM5 simulated data, a global orographic correction matrix is developed and applied to eliminate the influence of elevation variations, which theoretically gets rid of the influences of potential anthropogenic sources better than the old elevation correction method. A new gridding way is constructed and applied on both Four Corners and South Shānxī source areas to experiment on the effects of gridding methods. The new gridding method shows no significant difference, which proves the robustness of the emission estimation results. The latest EDGAR draft version 4.3.2 is applied, which includes the updated coal mine maps. The quantification results in Four Corners keep consistent, and show the EDGAR draft v4.3.2 in SS is possible to be overestimated.