CFC-11, a potent greenhouse gas and one of the main culprits in depleting the ozone layer, was set to be phased out by 2010. But starting in 2012 scientists noticed a considerable slowdown in the decline of global concentrations of CFCs.
The bulk of an increase of trichlorofluoromethane, better known as CFC-11, in the atmosphere has been found to originate from areas in eastern China, according to a new study published in the journal Nature.
The gas is believed to be stronger than carbon dioxide or methane in terms of its contribution to damaging effects from greenhouse emissions, the Guardian reports.
For the study, researchers from South Korea and Japan used air monitoring stations and created model simulations with the data they collected. They found the CFC-11 molecules originated from the northeastern Chinese provinces of Shandong and Hebei.
According to the study, CFC-11 emissions from these Chinese regions have increased by around 7,000 metric tons since 2013. This was a 110 percent increase compared emissions from 2008 to 2012, or 40 percent to 60 percent of the extra global CFC-11 emissions.
CFCs were once commonly used in refrigerators, aerosol cans and dry cleaning chemicals before they were banned in 1987 due to their contribution to the hole in the ozone layer over Antarctica under the Montreal Protocol.
In response to concerns regarding CFC emissions, a Chinese official was quoted by state-run news agency Xinhua as saying: "The Chinese government has no tolerance for any illegal production of ozone-depleting substances." (Next Animation via Reuters)