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Mysterious rise in banned ozone-destroying chemical shocks scientists

A sharp and mysterious rise in emissions of a key ozone-destroying chemical has been detected by scientists, despite its production being banned around the world.

Unless the culprit is found and stopped, the recovery of the ozone layer, which protects life on Earth from damaging UV radiation, could be delayed by a decade. The source of the new emissions has been tracked to east Asia, but finding a more precise location requires further investigation.

CFC chemicals were used in making foams for furniture and buildings, in aerosols and as refrigerants. But they were banned under the global Montreal protocol after the discovery of the ozone hole over Antarctica in the 1980s. Since 2007, there has been essentially zero reported production of CFC-11, the second most damaging of all CFCs.

The rise in CFC-11 was revealed by Stephen Montzka, at the US National Oceanic and Atmospheric Administration (NOAA) in Colorado, and colleagues who monitor chemicals in the atmosphere. “I have been doing this for 27 years and this is the most surprising thing I’ve ever seen,” he said. “I was just shocked by it.”

“We are acting as detectives of the atmosphere, trying to understand what is happening and why,” Montzka said. “When things go awry, we raise a flag.”
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Erik Solheim, head of UN Environment, said: “If these emissions continue unabated, they have the potential to slow down the recovery of the ozone layer. It’s therefore critical that we identify the precise causes of these emissions and take the necessary action.”

CFCs used in buildings and appliances before the ban came into force still leak into the air today. The rate of leakage was declining steadily until 2013, when an abrupt slowing of the decline was detected at research stations from Greenland to the South Pole.

Scientists then embarked on an investigation, published in the journal Nature, to find out the cause. The detective work began by assessing whether there had been changes in how the atmosphere distributes and destroys CFC-11 that could explain the changed measurements. But this factor was mostly ruled out and in the most recent data – 2017 – it appears to have played no role at all.

Next, the researchers looked at whether the release of CFC from older materials could have doubled, as required to explain the data. “But we don’t know of any folks who are destroying buildings at a much more dramatic rate than they were before,” said Montzka.

Lastly, the team considered whether the new CFC-11 was being produced as a by-product of some other chemical manufacturing process. But they ruled this out too, as the quantities involved are too high, representing a 25% rise in global emissions.

“You are left with, boy, it really looks like somebody is making it new,” said Montzka, who noted that the less damaging replacement for CFC-11 is more expensive to make.

“If the increased emissions were to go away [soon], it’s influence on the recovery date for the ozone layer would be minor,” he said. “If it doesn’t go away, there could be a 10-year delay, and if it continued to increase, the delay would be even longer.” The last option is a possibility, as if the new CFC-11 is being used in foams, then only a small fraction will have made it to the atmosphere so far and more could leak out for many years into the future.

Michaela Hegglin, at the University of Reading, UK, and not part of the research team said researchers had taken rigorous steps to rule out alternative explanations for the rise in CFC-11 when reaching their conclusion that new production must be occurring.

She said: “The study highlights that environmental regulations cannot be taken for granted and must be safe-guarded, and that monitoring is required to ensure compliance.” Prof Piers Forster, at the University of Leeds, UK, said: “This new study is atmospheric detective work at its finest.”

Paul Young, at Lancaster University, UK, said: “The Montreal Protocol has been rightly hailed as our most successful international environmental treaty, so the suggestion that there are possibly continued, unreported emissions of CFCs is certainly troubling and needs further investigation.”

Montzka said the world’s nations are committed to its enforcement. “I have a feeling that we will find out fairly quickly what exactly is going on and that the situation will be remedied,” he said. Even just the publicity about the new CFC-11 production could lead to its shutdown, he said: “Somebody who was maybe doing it purposefully will realise – oh, someone is paying attention – and stop doing it.”

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Op donderdag 17 mei 2018 11:06 schreef crystal_meth het volgende:
Wie zou het maken, en wie zou het gebruiken?

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Mysterious source of illegal ozone-killing emissions revealed, say investigators

A mysterious surge in emissions of an illegal ozone-destroying chemical has been tracked down to plastic foam manufacturers in China, according to an on-the-ground investigation published on Monday.

The chemical, trichlorofluoromethane or CFC-11, has been banned around the world since 2010 and is a potent destroyer of ozone, which protects life on Earth from UV radiation, and strong greenhouse gas. A shock rise in the gas in recent years was revealed by atmospheric scientists in May, but they could only narrow the source to somewhere in East Asia.

The Environmental Investigation Agency, a non-governmental organisation, has now identified widespread use of CFC-11 factories in China that make insulating foams. The EIA’s investigators identified factories that sold the chemicals needed for foam-making, then contacted and visited them.

“We were dumbfounded when out of 21 companies, 18 of them across China confirmed use of CFC-11, while acknowledging the illegality and being very blase about its use,” said Avipsa Mahapatra at the EIA. Furthermore, the companies said the use of CFC-11 was rife in the sector. “It was very clear. These companies, again and again, told us everybody else does this,” she said.

China is a major producer of the rigid polyurethane foams involved and the EIA calculates that if the illegal use of CFC-11 is pervasive in the 3,500 small- and medium-sized companies that make up the sector, then this would explain the surge. Without action, the CFC-11 emissions would delay the recovery of the planet’s ozone hole by a decade, scientists estimate.

“We didn’t know what on Earth someone would be using CFC-11 for – well, here’s one answer and that’s a surprise,” said Steve Montzka at the US National Oceanic and Atmospheric Administration in Colorado, whose team revealed the surge. “Despite efforts to get rid of this activity, it continues.”

He praised the EIA work, but cautioned that CFC-11 might be also produced by other activities and that this should not be ruled out: “If this one issue is targeted within China, we want to be sure that will take care of the problem.” New atmospheric measurements in east Asia should narrow down the total amount of CFC-11 being leaked and any hotspot locations in the next nine months, he said.

The EIA’s evidence has been passed to the Chinese government, which has already inspected and taken samples from some sites, and to officials at the Montreal Protocol (MP), the treaty that phased out ozone-killing chemicals. An MP working group is meeting in Vienna on 11 July and will consider the next steps.

“This week will be a critical moment for dialogue, resolve and action to ensure any illegal activities are fully investigated and urgently halted,” said Erik Solheim, the head of UN Environment, which hosts the MP. He said the EIA evidence was part of a wider body of scientific investigation taking place.

PU foams are used mainly as insulation in buildings, either sprayed into cavities or applied as solid panels, and are in high demand due to China’s construction boom. CFC-11 is easy to produce and $150 (£113) a tonne cheaper than the ozone-friendly alternative, according to the companies to which the EIA investigators spoke. The penalty in China for its use is a fine.

“The profit margins were very high, the demand was high and the risks were very low,” said Mahapatra. “That enabled these companies to use it so blatantly and is why we think this is so pervasive.”

A representative of one company, Aoyang Chemical Co, in Dacheng, Hebei province, told the EIA that 99% of its foams used CFC-11, bought from “shady and hidden” factories in Inner Mongolia. Another, from the nearby Wan Fu Chemical Co, said it was easy to avoid inspections: “When the municipal environmental bureau runs a check, our local officers would call me and tell me to shut down my factory. Our workers just gather and hide together.”

The EIA’s findings are supported by official Chinese government documents, with a 2016 report from environmental officials in Shandong province, a key region for foam production, stating: “There is still a large volume of illegally produced CFC-11 being used in the foam industry” and that its production is “highly concealed”. Other documents from Shandong showed one factory alone to have been producing 1,100 tonnes of CFC-11 in a year.

The EIA report acknowledges significant uncertainties in its calculation but believes it has been conservative in estimating 10,000-12,000 tonnes a year of CFC-11 leaking into the atmosphere from foam-making in China from 2012-17. The scientific study that revealed the surge estimated emissions between 8,000 and 18,000 tonnes over the same period.