Attribution of extreme weather events to climate change: possible, but tricky

Results of a 2011 World Climate Research Programme
study about the attribution of  extreme whether events

To what extent extreme whether events can be attributed to climate change in a way that can convince judges? An answer to this question is given by the article “Attribution of Weather and Climate-Related Extreme Events” written by Peter A. Stott, Myles Allen, Nikolaos Christidis, Randall Dole, Martin Hoerling, Chris Huntingford, Pardeep Pall, Judith Perlwitz, and Daithi Stone.

The article reflects the results of a conference held in 2011 by the World Climate Research Programme. The authors stress that at first sight conflicting findings of studies are often to be explained by the fact that the questions answered differ. They refer to the few published studies on particular events. E.g. there has been “an attributable human influence on the probability of some (including the Autumn 2000 flooding in the UK, and the 2003 European heat wave),” but “no substantial human influence on the magnitude of others (the Moscow heat wave of 2010 that).” The authors wonder whether future research will confirm the findings of these studies – and indeed a short time later in 2011 a study of the Potsdam Institute for Climate Change recently came to another conclusion for the Moscow heat wave. The authors conclude: “While such initial studies demonstrate the potential for event attribution they also highlight many of the challenges still to be faced […].”  And: findings on one region cannot be used for other regions.

You can find the full article here: http://conference2011.wcrp-climate.org/documents/Stott.pdf