More than 30 years ago, world governments dealt with an alarming hole in the ozone layer with the Montreal Protocol, which banned damaging chemicals including the chlorofluorocarbon CFC-11. But it looks like somebody failed to get the memo. Scientists say they've detected a mysterious rise in emissions of the ozone-destroying chemical from a source somewhere in East Asia, the Guardian reports. "I've been making these measurements for more than 30 years, and this is the most surprising thing I've seen," says lead researcher Stephen Montzka at the NOAA, which monitors chemicals in the atmosphere. "I was astounded by it, really."
"It really looks like somebody is making it new" in violation of international law, says Montzka. CFC-11, used as a refrigerant, is considered the second most damaging of the chemicals phased out under the 1987 Montreal Protocol. The US stopped making it in 1996, and worldwide production had reached almost zero by 2007. The substance is also a greenhouse gas that contributes to global warming. Alternatives have long been available, though they're more expensive to manufacture, the Washington Post reports. Scientists say that if the unauthorized emissions continue, there's a risk that the recovery of the ozone layer will be significantly slowed down. They're making it a priority to pinpoint the source of the emissions, which may require research flights over Asia.