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Someone makes a banned chemical that destroys the ozone layer, scientists suspect



Emissions of a banned ozone-depleting chemical are increasing, a group of scientists reported on Wednesday, suggesting someone could secretly produce the pollutant in violation of an international agreement.

CFC-11 emissions have increased by 25 percent since 2012, even though the chemical is part of a group of ozone deplants that were phased out under the 1987 Montreal Protocol.

"I've been doing these measurements for more than 30 years and that's the most surprising thing I've seen," said Stephen Montzka, a scientist at the National Oceanic and Atmospheric Administration who led the work. "I was really surprised . "

It is a depressing result for the nation, widely regarded as a global environmental success story, in which nations ̵

1; alerted by a growing" ozone hole "- are taking joint action to phase out chlorofluorocarbons. [196592002] The finding seems likely to initiate an international investigation into the mysterious source.

Officially, production of CFC-11 is expected to be at or near zero – at least that's what the nations have said and enforced by the UN agency, but scientists expect the emissions to rise that someone makes the chemical in violation of the ban.

"Someone cheats, "said Durwood Zaelke, founder of the Institute for Governance and Sustainable Development and expert on the Montreal Protocol, commenting on the new research. "There is a slight possibility that there is an unintentional release, but … they make it clear that there is strong evidence that this is actually produced."

But right now, scientists are not exactly sure who or where that person would be. A US observatory in Hawaii found CFC-11 mixed with other gases that were characteristic of a source from East Asia, but scientists could not further restrict the source.

Zaelke said he was surprised by the results. Not only because the chemical has long been banned, but also because there are already alternatives that make it hard to imagine what the market for CFC-11 would be today.

The research was led by researchers from the US Marine and Atmospheric Administration with the help of scientists in the Netherlands and the United Kingdom. Their results were published in the journal Nature.

There is a slim chance that there is an innocent explanation for the increase in CFC-11 emissions, says the scientist.

They have considered a number of alternative explanations for growth B. a change in atmospheric patterns that gradually remove CFC gases in the stratosphere, an increase in the rate of demolition of buildings containing old CFC-11 residues, or an unintentional production.

They concluded, however, that these sources could not explain the increase they have calculated in recent years to about 13 billion grams per year. The results suggest that the increased CFC-11 emissions are due to new production not reported to the UNEP ozone secretariat, which is incompatible with the agreed phase. "CFC production in the Montreal Protocol will continue until 2010 completed, "the researchers write.

CFC-11, which is mainly used for foams, can last up to 50 years in the atmosphere after release. It is destroyed only in the stratosphere, about 9 to 18 miles above the surface of the planet, where the resulting chlorine molecules cause a series of ozone-depleting chemical reactions. This loss of ozone in turn weakens our protection against UV radiation at the Earth's surface.

The chemical is also a powerful greenhouse gas that contributes to global warming.

The study's findings are "ecologically and politically quite serious," Robert Watson, a former NASA scientist who organized high-altitude deterrents in the Antarctic stratosphere in the 1980s to study ozone depletion.

"It's not clear why a country would like to start producing unintentional release, CFC-11, if low-cost substitutes are available for a long time," Watson continued.

"It is therefore essential that this outcome be discussed at the next ministerial meeting of governments in the face of ozone depletion depending on all countries that comply with the Montreal Protocol (and its adjustments and changes), with emissions globally zero

Watson suggested that airplane flights should not be required

Keith Weller, a spokesman for the United Nations Environment Program, who manages the Montreal Protocol, said the findings were reviewed by the scientific expert panel for the protocol (19659002) "If these emissions continue unabated, they could slow the recovery of the ozone layer," Weller said in a statement. "Therefore, it is crucial that we take stock of this science, identify the causes of these emissions, and take the necessary action."

The unannounced production of CFC-11 outside certain specific exemptions in the contract would be a "violation of international law," Weller affirmed, though he said the protocol was "non-punitive" and the remedy is likely to be a hearing with the offending party or the country.

But Zaelke thought the outcome could encourage tougher action.

"This contract can not afford not to follow its tradition and keep its compliance records."

"They will find the culprits, offending anyone who has worked on them for the last 30 years A tough group of people."

Overall, it is important to underline that the ozone layer is slowly recovering and ozone depleting substances still go back. But the apparent increase in emissions of CFC-11 has slowed the rate of decline by about 22 percent, the researchers found. This, in turn, will delay the recovery of the ozone layer and, in the meantime, make it more susceptible to other threats.

"Knowing how much time and effort and resources have been spent in ozone layer healing, and seeing that this is a shocker, frankly," said Montzka.

Chris Mooney deals with climate change, energy and the environment. He has reported on the Paris Climate Negotiations 2015, the Northwest Passage and Greenland Ice, and has authored four books on science, politics and climate change.

(c) 2018, The Washington Post


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