Fingers are being pointed at China for an observed increase in observed levels of chlorofluorocarbon CFC-11, which was phased out nearly a decade ago, according to a study published by Nature.
CFC-11 emissions have increased by 7,000 tonnes each year since 2013, and according to scientists, between 40 and 60 per cent of those emissions originated from China; a CFC derivative used in polyurethane insulating foams and refrigerators. CFC-11 is 5,000 times more potent than carbon dioxide at warming the Earth’s atmosphere.
The report used data sourced from air monitoring stations in South Korea and Japan, which gathered air samples as they drifted over the sea of Japan where they observed an extra 11,000 to 17,000 tonnes of CFC-11.
“We found a hot spot over somewhere near Shandong and Hebei provinces,” Dr Matt Rigby, an atmospheric chemist at the University of Bristol said. “It’s difficult to get this emissions signal without new production after 2010.”
He continued to explain that “the Korean data showed the magnitude of those pollution events started to increase after 2012.”
“Someone in that area started to emit more CFC-11 than they used to,” he said. “We looked at the rest of the network as well and didn’t find any evidence of increasing emissions from other places.”
The New York Times has reported previously that some Chinese factories were continuing to produce CFC-11 under a shroud of secrecy, while other manufacturers were reportedly bribing Chinese officials. Head of the United Nations Environment Program told the NYT investigation that illegal production of CFC-11 constituted “nothing short of an environmental crime which demands decisive action.”
Dr Rigby is hoping to gather data from his Chinese counterparts, to determine the culprits and the scope of the damage. “It would be great to see if data from China could help us locate the major emissions source more precisely,” he said, “or to see if there are emissions originating from more westerly or southerly areas of China, which the Gosan and Hateruma data are not sensitive to.”
China has made assurances to crack down on the production of CFC-11, however this has become difficult considering some manufacturers favoured the banned product because it was significantly cheaper, and of better quality than some of the alternatives.
Certain CFCs have been outlawed in one form or another as far back as the 1980s under the Montreal Protocol which aimed at tackling the production of propellants that were depleting the Earth’s ozone layer. The treaties were ratified by all 197 United Nations’ states, meaning they were the first universally-ratified treaty in UN history. CFC-11 was phased out under the Montreal Protocol in 2010.
They were commonly used in the production of fridges and building foams, which some arguments suggest could be the reason why there’s an observed resurgence. “Some people have proposed that maybe buildings made in the 70s and 80s were being demolished more rapidly and they could be releasing this pulse of CFC-11 into the air,” Dr Rigby said. “But we just didn’t find there was enough CFC-11 locked up in existing foams to make that plausible.”
In terms of the direct impact to the Earth’s ozone layer, NASA’s atmospheric chemist, Susan Strahan says that “it helps to point out where those emissions are coming from”, however, “the answer really depends on whether or not these emissions cease.”
“There’s potentially a bit of a tip of the iceberg situation here,” Strahan said.
“If it’s all locked up in foams now that have gone into buildings then it could be decades before we see the full amount released into the amount released into the atmosphere.”