China's Illegal Production of Banned Chemicals Could Delay Ozone Hole Recovery By Up to 18 Years

Emissions of banned gases being pumped into the atmosphere in China could delay the ozone's recovery, say scientists, and if action is not taken, it will take longer than expected for the hole above Antarctica to completely vanish.

A paper published in Nature Communications is the first piece of research to thoroughly assess the impact of trichlorofluoromethane on the ozone, projecting a delay of around 18 years under the very worst case scenario.

Trichlorofluoromethane (or CFC-11) is a colorless and odorless chlorofluorocarbon that can be used as an aerosol propellant or foam-blowing agent and was once the most commonly used refrigerant.

But since the Montreal Protocol (1987), its use has been phased out—as has the use of several other chemicals that were found to damage the ozone, otherwise known as ozone-depleting substances (or ODS). By 2010, that phase out was supposed to be complete.

And yet while use is technically illegal, scientists writing for Nature last year warned there had been an "unexpected and persistent increase" in CFC-11 emissions. This is linked to "unreported new production," most of which was found to be taking place in eastern China. More specifically, the provinces Shandong and Hebei, where 40 to 60 percent or more of the global rise in emissions originated from.

However, the cost to the ozone is unknown. This is because scientists do not know how much CFC-11 is being produced from these mysterious sources—or what it is produced for. (Products like solvents designed for an immediately emissive use have less of an impact that products like foam, which are designed for a non-emissive use.) Because of this, the researchers who conducted the study tested out a number of different scenarios based on the increase of emissions that had occurred within the last decade.

"So far the impact on ozone is small, but if these emissions indicate production for foam use, much more CFC-11 may be leaked in the future," wrote the study's authors.

Were the increase in emissions to continue for another ten years, ozone hole recovery could be delayed by a few years. Under a worst case scenario, the increase in emissions could delay recovery by up to 18 years, extending the time frame to 2078, the researchers found.

In comparison, the model simulations show full compliance with the Montreal Protocol, which should mean the ozone hole has pretty much recovered by 2065. Some metrics put an even better-case scenario at sometime in the early 2020s.

This worst case scenario is thought to be highly unlikely. Chinese authorities seem to be cracking down on the production of the ODS—last year, the government announced plans to introduce a national monitoring network to identify CFC-11 and other ozone-depleting chemicals.

Even smaller delays can be avoided. "We can get things back on track quite quickly. The implications for the ozone layer need not be too damaging," Martyn Chipperfield, an atmospheric scientist at the University of Leeds, U.K., and co-author of the study, told New Scientist.

ozone hole
New research suggests gases banned under the Montreal Protocol could delay recovery of the ozone hole by up to 18 years. The ozone hole pictured here is from October 10, 1986. Produced by NASA using data from the Nimbus 7 Total Ozone Mapping Spectrometer (TOMS) instrument. Interim Archives/Getty

The global community's response to fixing the hole in the ozone is a rare story of success, offering a shining example when it comes to future efforts to solving human-made environmental crises. A report published earlier this year found the hole may have been the smallest it has been since 1988.

"The Montreal Protocol is rightly seen as a seminal international agreement that has successfully led to decreasing levels of atmospheric chlorine and bromine and early signs of ozone recovery," the study's authors state.

"In this paper, we have shown that three decades since it was ratified, its continued success does face some challenges from recent unreported CFC-11 production. However, with swift action to curb this production and any other, the long-term success of the protocol will be ensured."

Indeed, things might already be heading towards the right track. "The latest NOAA results presented at the American Geophysical Union in San Francisco last week appear to show that the CFC-11 emissions may now be declining," Chipperfield told Newsweek. "Someone has got the message."

The article has been updated to include comments from Martyn Chipperfield.