Coal Mine Methane Emissions Tracker

This document outlines the methodology used by Ember for its Coal Mine Methane Emissions Tracker datatool, specifically detailing how confidence scores are assigned to national coal mine methane (CMM) emissions reported to the UNFCCC.

• Ember assigns a confidence score from 0 (low confidence) to 6 (high confidence) to each country's UNFCCC reported CMM emissions. This score is the sum of three categories, each scored from 0 to 2: the recency of reporting to the UNFCCC, the similarity of reported data to independent estimates, and the robustness of the estimation methods (UNFCCC Tier).
• The recency score is based on the date of the last report, with 2 points for reports in 2019 or more recently and 1 point for reports prior to 2019. A point is deducted if a country's coal production has changed by +/- 50% since the last UNFCCC reporting year.
• Similarity is measured by comparing UNFCCC reported emissions against three independent estimates: the IEA, GEM, and satellite data by Shen et al. (2023). Points are awarded based on the percentage difference: 2 points for less than 50% difference, 1 point for less than 100%, and 0 points for more than 100%. For countries emitting less than 5 thousand tonnes of methane per year, absolute difference is used instead of percentage to avoid bias.
• Robustness is scored based on the UNFCCC tier used for estimation and the proportion of underground versus surface mines. Tier 3 methodology combined with more than 50% of coal from underground mines earns 2 points, Tier 2 earns 1 point, and Tier 1 earns 0 points. Because surface mines do not measure methane emissions and have a maximum tier of Tier 2, countries with over 50% surface mining are capped at a maximum score of 2 for this category.
• Countries with reported or independently estimated CMM emissions of less than 1 kT per year are excluded from the scoring and designated as "not ranked" due to large uncertainties, although their data remains available on the Dashboard.

APA

Ember (2023). Coal Mine Methane Emissions Tracker. https://ember-energy.org/app/uploads/2023/11/Methodology_CMM-Emissions-Tracker.pdf

Chicago

Ember. Coal Mine Methane Emissions Tracker. 2023. https://ember-energy.org/app/uploads/2023/11/Methodology_CMM-Emissions-Tracker.pdf.

Wikipedia

{{cite report |author=Ember |title=Coal Mine Methane Emissions Tracker |date=2023 |url=https://ember-energy.org/app/uploads/2023/11/Methodology_CMM-Emissions-Tracker.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{ember2023coal, author = {{Ember}}, title = {{Coal Mine Methane Emissions Tracker}}, institution = {Ember}, year = {2023}, url = {https://ember-energy.org/app/uploads/2023/11/Methodology_CMM-Emissions-Tracker.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }