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Two provinces in China are causing a worrying increase in emissions of a globally banned chemical that damages the ozone layer that protects the Earth, according to a study released Wednesday that alarmed scientists who monitor the atmosphere of the planet.
The study, published in the magazine Nature, comes a year after another report reveals that air samples showed a surprising excess of a type of chlorofluorocarbon called trichlorofluoromethane, or CFC-11, since 2012.
This chemical manufactured, once it's been used to blow polyurethane in rigid foam insulation, it infiltrates the air and destroys the ozone molecules in the upper atmosphere. The ozone layer is essential for life because it limits the amount of harmful ultraviolet light reaching the planet's surface. CFC-11 is also a potent greenhouse gas, with about 4,750 times the heat retention potential of carbon dioxide.
The new report highlights the need to enforce international environmental agreements even when the dangers are clear and deep. And it reminds us that China's growing environmental challenges have global consequences.
"It's a big problem," said an official from the US State Department Wednesday. The official said the ministry plans to revise the report, but has not yet concluded that China is the source of the new emissions.
"If it's a problem in another country, we will also suffer from it"he said.
Any production and use of CFC-11 constitutes a violation of the Montreal Protocol, a 1987 agreement that: it has progressively eliminated these chemicals for the benefit of those who do not harm the atmosphere. The global agreement was reached after the scientists revealed the existence of an expanding hole in the ozone over Antarctica.
Last year's report has not identified the source of new problems beyond saying that it is very likely that they come from East Asia. But the authors of the new report have identified the provinces of Shandong and Hebei in eastern China. as a likely source of at least 40% of emissions.
The researchers based their findings on air samples from monitoring stations in South Korea and Japan. Sampling stations with instruments to determine the molecular components of air exhibited periodic peaks in CFC-11. The researchers combined this data with weather forecasts and observations of wind patterns. a series of computer models determine the most likely origin of emissions. The results highlighted the two Chinese provinces.
"When the wind blows in a straight line between this source and the measuring station, you see a peak"Lead author, Matt Rigby, Atmospheric Specialist at the University of Bristol.
"We are looking forward to working with our Chinese colleagues in the future to see if there are similar signals visible in their data"Rigby remarked.
The Montreal Protocol is often presented as a model of global cooperation for the protection of the environment and the what nations can do collectively to combat climate change, another crisis of the tragedy of the commons, caused by the burning of fossil fuels and other human activities.
The protocol authorities were alarmed by last year's report and asked for a "urgent action" to investigate the sources of emission and to apply the international agreement.
"We can not relax our vigilance for a second, we can not leave this problem unresolved"said Tina Birmpili, director of the UN Secretariat for the Environment in charge of ozone, last summer.
The protocol worked to a large extent as expected and the authors of the new report repeat this central message: the ozone layer continues to recover despite evidence of new emissions.
The problem is that recovery may occur more slowly than expected. CFC-11 levels in the atmosphere have not declined as fast as predicted by computer models.
There could have been relatively benign explanations. Much of the CFC-11 is already "stored" in the world of construction, in the form of an insulation that gradually filters the gas into the atmosphere. Rigby and his colleagues studied the possibility of new construction and replacement of the building stock, as well as the destruction of the old infrastructure may have released the chemical into the air.
But the numbers do not match. The most likely explanation is the new production and use of the chemicalhe explained.
Rigby said the new emissions of CFC-11 had the equivalent of global warming in all countries. CO2 emitted annually by human activity in the city of London.
Stephen Montzka, a scientist with the National Oceanic and Atmospheric Administration and co-author of both studies, said that the most recent discoveries leave important questions unanswered. Although researchers have detected about half of the disturbing CFC-11 emissions in the two Chinese provinces, Source details of other programs are still difficult to obtain.
"The guessing game is: where does the other half come from?" Montzka questioned, noting that the study only details the emissions in a limited region of China, which covers about one third of its population.
"Where does the rest come from? We do not know".
The increase in CFC-11 emissions raises further questions as to why someone would continue to manufacture it. The short answer is that CFC-11 is favored by some companies because it is cheaper and more effective than climate friendly alternatives. This is the conclusion of a survey published last year by the Environmental Research Agency, an environmental monitoring group Based in Washington.
The researchers discussed with representatives of 18 companies in 10 Chinese provinces that recognized the use of the banned chemical. Six of these companies were in Shandong and Hebei.
Following the release of new issues last year, the Chinese authorities have cracked down on the illegal use of CFC-11, seize 29 tons of chemicals and close dishonest factories, according to Avipsa Mahapatra, who works for the monitoring group.
However, she mentioned that the Nature indicates that this seized material represents only a fraction of what is produced and used. In addition, he pointed out that the researchers had discussed with companies that concealed the use of CFC-11, for example: expose legal chemicals that can be shown to government inspectors.
"We are just beginning to understand the magnitude of the problem"he commented.
Montzka expressed his perplexity over the return of CFC-11.
"The phasing out was supposed to take place in 2010 and I think it's like that"he said. "Why did he come back?"
This could be a case in which the early detection of illegal production could lead to actions to stop its use, which would minimize the impacts on the ozone layer, detailed. But since the chemical is usually filtered from the moss over the decades, says Montzka, the total magnitude of the problem remains unknown.
"It is possible that we have only seen the tip of the iceberg so far"said Montzka. "If what we have detected actually represents only a small fraction of the new illegal production produced since 2010, the problem could be bigger than what we have detected so far. "
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