Mysterious new man-made gases pose threat to ozone layer…

Image Credits: NOAA – National Weather Service – Climate Prediction Center

By WUWT Regular “Just The Facts”

On the heels of Andrew Dessler’s Ozone Hole tweet, we have from the BBC:

“Researchers from the University of East Anglia have discovered evidence of four new gases that can destroy ozone and are getting into the atmosphere from as yet unidentified sources.”

“Scientists have identified four new man-made gases that are contributing to the depletion of the ozone layer.

Two of the gases are accumulating at a rate that is causing concern among researchers.”

“Other scientists acknowledged that while the current concentrations of these gases are small and they don’t present an immediate concern, work would have to be done to identify their origin.

“This paper highlights that ozone depletion is not yet yesterday’s story,” said Prof Piers Forster, from the University of Leeds.

“The concentrations found in this study are tiny. Nevertheless, this paper reminds us we need to be vigilant and continually monitor the atmosphere for even small amounts of these gases creeping up, either through accidental or unplanned emissions.

“Of the four species identified, CFC-113a seems the most worrying as there is a very small but growing emission source somewhere, maybe from agricultural insecticides. We should find it and take it out of production.”

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The paper “Newly detected ozone-depleting substances in the atmosphere” Laube et al., paywalled, can be found here:

“Ozone-depleting substances emitted through human activities cause large-scale damage to the stratospheric ozone layer, and influence global climate. Consequently, the production of many of these substances has been phased out; prominent examples are the chlorofluorocarbons (CFCs), and their intermediate replacements, the hydrochlorofluorocarbons (HCFCs). So far, seven types of CFC and six types of HCFC have been shown to contribute to stratospheric ozone destruction1, 2. Here, we report the detection and quantification of a further three CFCs and one HCFC.”

“Our observations on air samples collected in remote regions of the atmosphere show the presence of four previously undetected ozone-depleting substances (ODSs). We have identified and quantified CFC-112 (CFCl2CFCl2), CFC-112a (CF2ClCCl3), CFC-113a (CF3CCl3) and HCFC-133a (CF3CH2Cl) in the atmosphere (Fig. 1). We have reconstructed their past abundances from air extracted from deep polar firn, which can provide a natural archive of atmospheric composition up to about a century back in time5. Our firn air measurements suggest that all four newly reported compounds are anthropogenic (see also Supplementary Information), with insignificant atmospheric abundances before the 1960s.”

For reference, the images the head of this article show the current Northern “Ozone Hole” within the Northern Polar Vortex, at 10 hPa/mb – Approximately 31,000 meters (101,700 feet). Draw your own conclusions…