Researchers at the University of East Anglia in cooperation with other universities and publishing this month in the journal Nature Geoscience say they have identified four new ozone damaging man made gases, three types of CFCs and one HCFC, that could damage the ozone layer and contribute to global warming.
To determine this, the researchers looked at air samples captured in the 1970s by, for instance, analyzing air bubbles that have been trapped in Greenland’s snowpacks, as well as analyzing samples that were originally harvested by aircraft flying 13 miles above Europe.
The newly identified compounds, which until now had not been recorded, are not among the 13 CFCs and HCFCs that are currently regulated under the United Nation’s landmark 1987 Montreal Protocol which serves to control and in many cases ban CFC production. Furthermore, samples show that none of the compounds were present before the 1960s, meaning that (relatively) modern manufacturing may be the culprit.
In total, the researchers believe that around 74,000 tons of the four gases are now present in the atmosphere. That’s only a fraction of the millions of tons of CFC gases that were released during the 1980s, but the concentration of at least two of the gases appears to be rising quickly, meaning that current restrictions aren’t delaying them.
Where could they be coming from if not from manufacturing, then? Well, because of the Montreal Protocol’s quite broad exemptions, it doesn’t necessarily mean that the CFC and HCFCs identified by this study aren’t still being emitted legally. There’s also the possibility that they could be being produced illegally as well.
All that aside, the researchers believe that at least one of the CFCs, known CFC113a, may be being used as a component of agricultural pesticides, something which does not necessarily fall under the Montreal Protocol or other restrictions.
The gases also appear to be strong insulating gasses. As CFCs are many more times insulating than carbon dioxide, that’s a problem because they could trap heat and raise global temperatures if enough of the gases got into the atmosphere. Also, the researchers believe that there are potentially dozens more compounds that have yet to be properly identified, meaning that collectively they could pose a serious threat not just to the ozone layer itself but also undermine the fight against global warming.
“There are definitely more out there,” Dr Johannes Laube, at the University of East Anglia, is quoted as saying. “We have already picked up dozens more. They might well add up to dangerous levels, especially if we keep finding more.”
Despite these scary sounding facts, it’s important to put the issue in context: there’s no immediate danger and, fortunately, this research has identified the compounds early on so they can be tracked down and, hopefully, action can be taken.
“While these newly discovered gases can, in theory, cause some damage to the ozone layer, their combined abundance is over 500 times smaller than that of the main ozone-destroying compounds in the 1990s,” points out co-researcher Martyn Chipperfield, a professor of atmospheric chemistry at the University of Leeds. “These new observations do not present concern at the moment, although the fact that these gases are in the atmosphere and some are increasing needs investigation.”
What should we take from this research, then? The main thing that the researchers appear to want to get across is that ozone depletion is not something consigned to the history books. It is still a threat and there is no room for complacency.
The researchers are also calling on international governments to look again at the landmark Montreal Protocol and discuss how it can be improved as, despite the improvements that have been made in recent years, its reach is not yet wide or tough enough.
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