Reported coal mine methane emissions
The Global Coal Mine Tracker (GCMT) compiles data from company and government sources which report annual methane emissions figures at the mine scale. The data include values automatically extracted from national reporting agencies, as well as values taken from company sources such as annual and sustainability reports. These reports are identified on a mine-by-mine basis during the course of GCMT research. In cases where a mine has reported emissions data in both an annual report and to a government agency, the latter is provided. Individual references for each mine can be found on the mine’s GEM.wiki page.
In general, data for reported mines are linked with GCMT assets on the bases of name, ownership, location, and where possible, unique IDs from government agencies. For the countries with comprehensive data from reporting agencies, the specific automated extraction and linkage strategies are described below. In cases where countries reported emissions in CO2e (versus methane) conversion factors are also enumerated below. To calculate the “Reported Coal Mine Methane Emissions (thousand tonnes CO2 equivalent)” column, GEM multiplied the values in the “Reported Coal Mine Methane Emissions (thousand tonnes CH4)” column by 83, representing the 20-year GWP for fossil methane drawn from the sixth IPCC assessment report.
Australia
Australian emissions data are extracted from the Safeguard Mechanism database as of 5/5/2026. They include data based on measurements taken between June 2024 and June 2025. The data in the Facility name field in the Safeguard Mechanism data are matched on a mine-by-mine basis with GCMT assets using a combination of name, location, and operator. The data in the GHG Methane field is reported in metric tons CO2e and multiplied by 0.028 to convert to kilotons methane. Some mines which match to multiple different GEM mine assets are omitted in this version of the GCMT.
United States
The United States’ emissions data are extracted from the Greenhouse Gas Reporting Program, Subpart FF data as of 5/5/2026. The latest available data for the GHGRP at that time was 2023. Mines are matched to GCMT assets on a mine-by-mine basis using a combination of MHSA ID, name, location and operator. Quarterly data in the ‘Total Quarterly Net Methane Emissions to the Atmosphere - Calculated Facility Total Quarterly Net CH4 emissions to the atmosphere from the mine’ ( tot_qrtly_ch4) field are summed to provide an annual figure and then divided by 1,000 to produce the final figure reported in the GCMT in kilotons.
Poland
Polish emissions data are drawn from Instrat’s Lignite and hard coal mining database v5.5 (sheet “1_KOPALNIE_MINES”) as of 5/5/2026. Instrat draws data from KOBiZE (Krajowy Ośrodek Bilansowania i Zarządzania Emisjami), the National Centre for Emissions Management in Poland. Mines are matched to GCMT assets on a mine-by-mine basis using a combination of name, location and operator. The latest available year of emissions data are reported, taken from the “Methane emissions into atmosphere [year]” column. These figures are divided by 1,000 to produce the final figure reported in the GCMT in kilotons methane.
Canada
Canadian emissions data are downloaded manually from the Canadian Greenhouse Gas Reporting Program data as of 5/5/2026. The latest available data for the GHGRP at the time is 2024. Mines are matched to GCMT assets on the basis of Canadian GHGRP ID, name, location and operator. Data in the CH4 field are multiplied by .028 to convert from tCO2e to kt methane.
