Methane emissions from coal mining are growing

Monday, 7 December 2020: 05:57
Nazar Kholod1, Meredydd Evans1, Raymond Pilcher2, Volha Roshchanka3, Felicia Ruiz4, Michael Coté5 and Ron Collings5, (1)Pacific Northwest National Laboratory, Joint Global Change Research Institute, Richland, WA, United States, (2)Raven Ridge Resources, Grand Junction, CO, United States, (3)US Environmental Protection Agency, Climate Change Division, Washington, DC, United States, (4)US Environmental Protection Agency (former), Washington, DC, United States, (5)Ruby Canyon Engineering, Grand Junction, CO, United States
Coal mines are one of the largest sources of anthropogenic methane emissions. As the world produces more coal, coal mines get deeper every year, and methane emissions grow with the increasing mining depths. Mine operators also abandon coal mines, but coal strata in these old mines still emit methane into the atmosphere. This study uses measurement data on mine depth, gas content of coal, and other data from key coal producing countries to estimate methane emissions from active (CMM) and abandoned mines (AMM). This methodology can help more accurately estimate global emissions from coal mining because it takes a comprehensive look at emissions, even in cases where there are gaps in direct measurement and official reporting. For example, few countries measure their abandoned mine methane emissions. A detailed assessment shows that coal mining-related methane emissions are higher than previous studies have showed. The methodology can also be used to estimate CMM and AMM emissions through 2100 under various coal production scenarios and to understand the potential range of uncertainty in current emissions estimates. To reduce uncertainties in methane emission estimates, more efforts are needed to improve reporting and cross-checking through measurement.