Emissions from eastern mainland China account for at least 40-60% of the global rise in trichlorofluoromethane (CFC-11) emissions since 2013, according to a study published in Nature this week. This rise is likely to be the result of new production and use, which is contrary to the Montreal Protocol agreement to globally phase out CFC production by 2010.
The concentration of CFC-11 in the atmosphere has declined substantially since the mid-1990s. However, last year it was reported that there has been a slowdown in this decline since 2012. It was suggested that global CFC-11 emissions have increased, but the locations of the sources responsible for this rise had not been identified.
Sunyoung Park, Matt Rigby and colleagues combined atmospheric observations from Gosan, South Korea, and Hateruma, Japan, with global monitoring data and atmospheric chemical transport models to investigate the source of the increase. The authors report that CFC-11 emissions from eastern mainland China were approximately 7,000,000 kilograms per year higher between 2014 and 2017 than 2008-2012. They show that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei, and that these emissions are probably the result of new, unreported production and use.
Further investigations will be needed to determine the processes that have led to the increase and the magnitude of any associated CFC-11 production.
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