This link is shown by an analysis published in the latest issue of Science. An international team of researchers, headed by Holland's Guus Velders and including the chemistry Nobel laureate Mario Molina and Empa researcher Stefan Reimann, investigated the unintentional (positive) climate effects resulting from the Montreal Protocol. Since the year 2000 the radiative forcing (a measure of the effect on the climate of chemical substances) of all ozone-depleting substances including CFCs has remained at a more or less constant value of 0.32 W/m2, compared to a value of 1.5 W/m2 for CO2. Had the Montreal Protocol recommendations not been implemented, today's value would be approximately double this figure, i.e. 0.65 W/m2. Putting things another way, the CFC ban has prevented the equivalent of 10 billion tonnes of CO2 being emitted into the atmosphere in 2010, five times the annual reduction target set by the Kyoto Protocol.
Velders, Reimann and their co-authors fear that this positive effect will soon be negated by HFC emissions, which are currently increasing at 10 to 15% annually. In their article they state that the HFC contribution to climate change can be viewed as an unintended negative side effect of the Montreal Protocol. At the moment the effect is still small about 0.012 W/m2 for all CFC substitutes combined. But it is beyond question that radiative forcing due to HFCs will rise significantly in future as a result of increasing demand and production for these su
|Contact: Dr. Stefan Reimann|
Swiss Federal Laboratories for Materials Science and Technology (EMPA)