Thursday, May 24, 2018

Cheating the Planet's Health with CFCs

Scientists at NOAA say someone on Earth is manufacturing a banned chemical, CFC-11, that is depleting the protective ozone layer.  Emissions of CFC-11 have climbed twenty-five percent since 2012 despite the prohibition on the manufacture and use in the Montreal Protocol of 1987.  In that agreement, nations took action to stop the depletion of Earth's ozone layer which protects the planet from ultraviolet radiation by phasing out chlorofluorocarbons (CFCs).  Emissions of the chemical should be near zero as reported to the organization responsible for enforcement of the international agreement.  Scientists say the increase in detected emissions is strong evidence somebody, somewhere is manufacturing it.  A U.S. observatory in Hawaii found CFC-11 mixed in with other gases that were characteristic of a source coming from somewhere in eastern Asia, but scientists could not narrow the area down any further.  The research results were published in the journal, Nature.  The results are likely to precipitate and investigation into the source of the emissions.

Alternatives exist for chlorofluorocarbons, so it is not easy to understand where a market for the chemical could exist.  CFC-11 was used for foam and can last up to 50 years in the atmosphere.  It is broken down only in the upper stratosphere, where the constituent chlorine atoms engage in a series of ozone destroying reactions.  If the emissions continue unabated, ozone layer recovery could be threatened again. [image credit: NASA/Goddard Space Flight Center] The releases have slowed the rate of decrease in  ozone destroying chemicals by 22%