China, already the world’s leading emitter of human-caused greenhouse gases, continues to pump increasing amounts of climate- changing methane into the atmosphere despite tough new regulations, according to research led by Scot Miller, an assistant professor of environmental health and engineering at Johns Hopkins.
Miller’s study, published in Nature Communications in January, indicated that although China’s government had vowed to curb the nation’s methane emissions, it hasn’t made good on this promise.
China is the world’s largest producer and consumer of coal, which accounts for approximately 72 percent of the country’s electricity generation. While data show that coal production increased in China, it has been unclear until now how much methane gas, or CH4, has increased. Regulations enacted by China in 2010 require all mines to use methane that they produce for heating or electricity generation, or to flare it.
To examine how China’s methane emissions have trended from 2010 to 2015, the research team used data from the Greenhouse Gases Observing Satellite, launched by the Japan Aerospace Exploration Agency in 2009.
Miller and team found that methane emissions rose by approximately 1.1 teragrams each year from 2010 to 2015 in China, resulting in about a 50 percent higher level of annual CH4 emissions by the end of the period. This increase is comparable to total emissions from countries like Russia or Brazil, and it accounts for 11 to 24 percent of the world’s total increase.
“China has received a lot of press coverage over the past few years for its efforts to enact greenhouse gas regulations and become a leader on climate change, but the numbers show that China’s methane regulations, in particular, have not had any detectable impact on their emissions,” says Miller.
Looking forward, Miller’s research team will examine how China can most effectively implement its methane emission policies and improve air quality.