3/10/14, "Research Reveals New Man-Made Ozone-Depleting Gases in the Atmosphere," scitechdaily.com
"New research from scientists at the University of East Anglia reveals four new man-made gases in the atmosphere that are contributing to the destruction of the ozone layer.
New research published in the journal Nature Geoscience reveals that more than 74,000 tonnes of three new chlorofluorocarbons (CFCs) and one new hydrochlorofluorocarbon (HCFC) have been released into the atmosphere.
Scientists made the discovery by comparing today’s air samples with air trapped in polar firn snow – which provides a century-old natural archive of the atmosphere. They also looked at air collected between 1978 and 2012 in unpolluted Tasmania.
Measurements show that all four new gases have been released into the atmosphere recently – and that two are significantly accumulating. Emission increases of this scale have not been seen for any other CFCs since controls were introduced during the 1990s. But they are nowhere near peak CFC emissions of the 1980s which reached around a million tonnes a year.
Lead researcher Dr Johannes Laube from UEA’s School of Environmental Sciences said: “Our research has shown four gases that were not around in the atmosphere at all until the 1960s which suggests they are man-made.”
“CFCs are the main cause of the hole in the ozone layer over Antarctica. Laws to reduce and phase out CFCs came into force in 1989, followed by a total ban in 2010. This has resulted in successfully reducing the production of many of these compounds on a global scale. However, legislation loopholes still allow some usage for exempted purposes.
“The identification of these four new gases is very worrying as they will contribute to the destruction of the ozone layer. We don’t know where the new gases are being emitted from and this should be investigated. Possible sources include feedstock chemicals for insecticide production and solvents for cleaning electronic components.
“What’s more, the three CFCs are being destroyed very slowly in the atmosphere – so even if emissions were to stop immediately, they will still be around for many decades to come,” he added.
This research has been funded by the Natural Environment Research Council (NERC), the National Centre for Atmospheric Science (NCAS), the European Union, and the Commonwealth Scientific and Industrial Research Organisation (CSIRO).
Publication: Johannes C. Laube, et al., “Newly detected ozone-depleting substances in the atmosphere,” Nature Geoscience, 2014; doi:10.1038/ngeo2109
Source: University of East Anglia"
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"Climategate," Mother Nature Network
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""We were certainly surprised to find so many previously undetected gases out there, and we keep finding more," Johannes C. Laube of the University of East Anglia, Norwich, U.K., said."
3/31/14, "Researchers Find Five Previously Undetected Greenhouse Gases," AccuWeather.com, Mark Leberfinger
"Two new scientific research efforts have uncovered five new man-made greenhouse gases that may play a role in climate change and ozone depletion.
Increasing greenhouse gases trap additional heat in the lower atmosphere, which results in higher surface temperatures, AccuWeather.com Senior Meteorologist Brett Anderson said.
"Climate models certainly account for the increase in greenhouse gases," Anderson said....
The discovery of three chlorofluorocarbons (CFCs) and one hydrochlorofluorocarbon (HCFC) were reported online March 9, 2014, in the journal "Nature Geoscience" by researchers from the United Kingdom, Germany, Australia, France and the Netherlands.
"We were certainly surprised to find so many previously undetected gases out there, and we keep finding more," Johannes C. Laube of the University of East Anglia, Norwich, U.K., said.
At their current concentrations, the new gases do not pose a major threat to the ozone layer as they are tens to hundreds of times smaller than those of the known seven types of CFCs, which are still around, he said.
"What is worrying is the continuing increase of two of the gases, in particular that of CFC-113a, which is a) Much more dangerous to ozone than HCFC-133a, and b) has started to accelerate its increase after 2010. If such a trend were to continue, it would become a serious threat to the ozone layer within the next decade," Laube said.
Laube's team analyzed unpolluted air samples from Tasmania between 1978 and 2012 and air samples from polar firn snow from Greenland in 2008. Polar firn snow is the hard snow on top of glaciers and can be up to 100 meters thick.
"As new snow falls on top of it, air bubbles are being trapped inside," Laube said. "If you drill into the firn, the deeper you get, the further you go back in time. At the bottom of the firn, the air can be up to 100 years old. So if we are interested in a particular gas in the atmosphere, this firn air allows us to reconstruct (using firn models) its temporal evolution over the last century."
The discovery of the new gases may have exposed a loophole in the "Montreal Protocol on Substances that Deplete the Ozone Layer."
It doesn't mean that the gases have been illegally introduced to the atmosphere in violation of the protocol, Laube said. Production of CFCs have been banned with limited exceptions since 2010, while some production of HCFCs continue.
"Our research has so far focused on the overall concentrations and trends of these gases in the global atmosphere, so we haven't attempted to pinpoint sources yet," Laube said. "We can currently only speculate on which are the major usages, but have found a few indications.""... via Rush Limbaugh
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