Loopholes in CFC ban pose new threat to ozone layer, say scientists

Researchers at the University of East Anglia have identified four chemicals permitted under the Montreal Protocol that appear to be slowing the recovery of the ozone hole.

NASA/Ozone Hole Watch
The area of the ozone hole, such as in October 2013 (above), is one way to view the ozone hole from year to year. However, the classic metrics have limitations, NASA scientists say.

Four new man-made, ozone-destroying chemicals have been discovered in the upper atmosphere, and appear to be slowing the recovery of the ozone hole, according to a new report.

The ozone hole over Antarctica has been gradually healing ever since an international treaty known as the Montreal Protocol began limiting the production of ozone-depleting chemicals in 1989. These chemicals, known as chlorofluorocarbons (CFCs), were commonly used in refrigerators, air conditioners and aerosols until they were found to react with and break down ozone molecules in the Earth's protective ozone layer. The treaty was created to significantly cut CFC emissions and allow the ozone hole to completely close, potentially by 2050.

In 2010, a total ban on CFCs was put in place, but certain loopholes still exist in the Montreal Protocol that allow trace amounts of the chemicals to be used in the production of certain products, including some types of insecticides and solvents used to clean electronic equipment. [Top 10 Ways to Destroy Earth]

Now, researchers based at the University of East Anglia in the United Kingdom have calculated that these loopholes — previously thought to be relatively insignificant — have actually allowed more than 74,000 metric tons (about 82,000 tons) of three previously unknown CFCs, and one related compound known as an HCFC, to be released into the atmosphere. While this quantity is far smaller than peak CFC emissions in the 1980s, it is still a significant quantity that could slow the recovery of the ozone hole, the team reports today (March 9) in the journal Nature Geoscience.

"In comparison to the 1980s, it is minor — it is not a threat to the ozone layer just yet," said study co-author Johannes Laube.

But emissions of two of the compounds appear to have accelerated in recent years, which could result in more serious degradation of the ozone layer within a decade, Laube told Live Science.

To quantify the emissions of the new compounds, the researchers compared modern air samples with nearly century-old air samples trapped in old, compacted snow (known as firn snow) from Greenland. The team did not detect any of the four new compounds in snow from before the 1960s, which suggests that the compounds were man-made.

More recent samples were collected from a relatively unpolluted region of Tasmania from 1978 to 2012. The team has also been systematically collecting hundreds of air samples in each of the past five years from commercial air flights around the world.

It is still unclear whether the newly detected emissions are related to legal loopholes in the Montreal Protocol, or illegal chemical production, the team said. Regardless, the researchers think their findings call for a thorough examination of possible sources, and may offer a good opportunity to tighten the loopholes in the treaty, Laube said.

The team next plans to more closely analyze their aircraft samples to try to pinpoint sources of emissions, which they currently can only trace generally to the Northern Hemisphere.

Follow Laura Poppick on Twitter. Follow us @livescience, Facebook & Google+. Original article on Live Science.

Copyright 2014 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

You've read  of  free articles. Subscribe to continue.
Real news can be honest, hopeful, credible, constructive.
What is the Monitor difference? Tackling the tough headlines – with humanity. Listening to sources – with respect. Seeing the story that others are missing by reporting what so often gets overlooked: the values that connect us. That’s Monitor reporting – news that changes how you see the world.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.

QR Code to Loopholes in CFC ban pose new threat to ozone layer, say scientists
Read this article in
QR Code to Subscription page
Start your subscription today