A massive plume of methane, the potent greenhouse gas that’s a key contributor to global warming, has been identified in China’s biggest coal production region.
The release in northeast Shanxi province is one of the largest that geoanalytics company Kayrros SAS has so far attributed to the global coal sector and likely emanated from multiple mining operations.
Details captured in European Space Agency satellite data show the plume about 90 kilometers (56 miles) east of Shanxi’s capital Taiyuan, in Yangquan City. The area has 34 coals mines, according to the Shanxi Energy Bureau.
Shanxi’s Department of Ecology and Environmental, the province’s Energy Bureau and China’s Ministry of Ecology and Environment didn’t respond to requests for comment. The National Development and Reform Commission didn’t respond to a fax.
The emissions rate needed to produce the plume observed in the June 18 satellite image would be several hundred metric tonnes an hour, according to Kayrros. For comparison, a 200-tonne per hour release would have roughly an equivalent climate warming in the first two decades as 800,000 cars driving at 60 miles an hour, according to the Environmental Defense Fund.
China is both the world’s largest producer and consumer of coal. The industry presents the nation’s biggest opportunity to mitigate methane emissions, according to a United Nations assessment. In March, China’s latest five-year plan included, for the first time, a pledge to contain the gas that traps roughly 80 times more heat than carbon dioxide in the initial 20 years after it is released.
President Xi Jinping has outlined an ambition for the country to start reducing coal use from 2026 on its way to a broader goal to peak greenhouse gas emissions by the end of the decade and reach carbon neutrality by 2060.
China’s foreign ministry spokesman Wang Wenbin told reporters during a regular press briefing on Monday he wasn’t aware of the release and said the country is committed to low-carbon development.
Efforts to curtail coal use to have largely focused on the large amount of CO₂ generated when it’s burned. But mining the fuel is also problematic, because producers frequently release methane trapped in underground operations to lower the risk of explosion.
“Many existing coal mines are under poor management” in China, said Li Shuo, a climate analyst at Greenpeace East Asia. “There is much catching up to do to better monitor the sources and scale of methane emissions.”
Methane can continue leaking long after mines have been closed or abandoned, and the industry is expected to account for about 10% of man-made emissions of the gas by the end of the decade, according to the Global Methane Initiative.
To achieve its 2060 carbon neutral goals, China should create an investment and financing system that tackles methane reductions, the Environmental Defense Fund said in a report.
It can also make sense for miners themselves to take extra steps to capture methane emissions, as the gas can be used for power generation, coal drying or as supplemental fuel, according to the U.S. Environmental Protection Agency.
The analysis of the Shanxi plume follows earlier work to identify methane releases in countries including Russia and South Africa, as scientists begin to pinpoint the biggest sources of the emissions.
Existing data isn’t yet globally comprehensive, and satellite observations can be impacted by cloud cover, precipitation and varying light intensity. Satellites can also have difficulty tracking offshore emissions and releases in higher latitudes.