Banned Ozone-Destroying Chemicals Still In Production, Scientists Baffled

The loss of ozone is weakening protection from UV rays on the planet and CFC-11 is also a powerful greenhouse gas causing global warming

Trichlorofluoromethane (CFC-11) is the second-most abundant ozone-depleting gas in the atmosphere and a member of the family of chemicals most responsible for the giant hole in the ozone layer that forms over Antarctica each September. Use of the chemical was banned in 2010 via the Montreal Protocol, an global agreement made to protect the environment.

"We're raising a flag to the global community to say, 'This is what's going on, and it is taking us away from timely recovery of the ozone layer", said NOAA scientist Stephen Montzka, the study's lead author. That speculation is due to increased CFC-11 emissions, a big issue that could delay ozone restoration efforts and contribute to a warming planet. The chemical, called CFC11, was used for making foam, degreasing stains and for refrigeration. However, starting in 2013, emissions of CFC11 have been rising again, according to a study by a team at the National Oceanic and Atmospheric Administration, published in Nature magazine. This means that the total concentration of ozone-depleting chemicals, overall, is still decreasing in the atmosphere. Production was banned, emissions fell and the hole slowly shrank.

The regulations were initially reflected by the data, with the amounts detected in the atmosphere sinking at a constant rate between 2002 and 2012. This conclusion was confirmed by other changes recorded in NOAA's measurements during the same period, such as a widening difference between CFC-11 concentrations in the northern and southern hemispheres-evidence that the new source was somewhere north of the equator. When the researchers examined measurements from atop Mauna Loa in Hawaii, they found that other industrial emissions are also increasing. "Further work is needed to figure out exactly why emissions of CFC11 are increasing, and if something can be done about it soon". Under the treaty's requirements, nations have reported less than 500 tons of new CFC-11 production per year since 2010.

Under the Montreal Protocol, the world agreed to begin phasing out CFC-11, ending its production altogether by 2010.

Last fall, it was reported that the hole in the Earth's ozone layer had shrunk to its smallest size since 1988, which was great news.

The 1987 Montreal Protocol phased out ozone-damaging chemicals like CFC-11 worldwide.

To put this in perspective, at peak emissions in the 1980s, the world was producing 350,000 tons of CFC-11 each year, before dropping to 54,000 tons per year at the turn of the century.

"If the emissions were to persist, then we could imagine that healing of the ozone layer, that recovery date, could be delayed by a decade", said Dr Montzka.

"If these emissions continue unabated, they have the potential to slow down the recovery of the ozone layer", Weller said in a statement.

Keith Weller, a spokesman for the United Nations Environment Program, which helps implement the protocol, said the findings would be presented to the parties to the agreement for review.

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