"I've been making these measurements for more than 30 years, and this is the most surprising thing I've seen", the paper's lead author, Stephen Montzka, told The Washington Post's Chris Mooney. A USA observatory in Hawaii found CFC-11 mixed in with other gases that were characteristic of a source coming from somewhere in east Asia, but scientists could not narrow the source down any further.
Emissions of a banned, ozone-depleting chemical are on the rise, a group of scientists reported Wednesday, suggesting someone may be secretly manufacturing the pollutant in violation of an worldwide accord.
Emissions of CFC-11 increased by 25 percent in 2012, despite the fact that the chemical substance is part of a group of pollutants for ozone, which were banned under the Montreal Protocol of 1987. "In the end, we concluded that it's most likely that someone may be producing the CFC11 that's escaping to the atmosphere", he said. The growth in the size of the ozone "hole" over Antarctica has slowed. "Further work is needed to figure out exactly why emissions of CFC-11 are increasing and if something can be done about it soon". Recognised as an ozone depleter under the Montreal Protocol, R11 was banned along with other common CFC refrigerants R12 and R502. A smaller amount of CFC11 also exists today in older refrigerators and freezers.
Despite the increase in CFC-11 emissions, its concentration in the atmosphere continues to decrease, but only about half as fast as the decline observed a few years ago, and at a substantially slower rate than expected.More news: Spanish GP highlights include a spectacular crash, not much overtaking
But "continued increase in global CFC-11 emissions will put that progress at risk".
Precise measurements of global atmospheric concentrations of CFC-11 made by NOAA and CIRES scientists at 12 remote sites around the globe show that CFC-11 concentrations declined at an accelerating rate prior to 2002 as expected.
However, if no action is taken on the new source of emissions, it could be highly significant.
This treaty saw the production of CFCs, including CFC-11, banned in developed countries in the mid 1990s and in the rest of the world by 2010.More news: SC upholds Khaleda's bail in graft case
"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.
However, it took many decades for scientists to discover that when CFCs break down in the atmosphere, they release chlorine atoms that are able to rapidly destroy ozone molecules. Emissions of this CFC to the atmosphere reached about 386,000 tons per year at their peak later in the decade.
"The ozone layer remains on track to recovery by mid-century", the UN Environment Programme (UNEP) said in a statement, reacting to the findings.
The findings of Montzka and his team of researchers from the Cooperative Institute for Research in Environmental Sciences (CIRES), the United Kingdom, and the Netherlands, represent the first time that emissions of one of the three most abundant, long-lived CFCs have increased for a sustained period since production controls took effect in the late 1980s. If not remedied soon, however, substantial delays in ozone layer recovery could be expected.More news: Vladimir Putin says, Russian warships permanently on duty in Mediterranean
But Mr. Doniger noted that the Montreal Protocol, which has been signed by almost 200 countries, has a strong track record of compliance, with countries often reporting their own violations.