Evidence indicates link between weather extremes and global warming

No boat tickets today! - Rhine in flood January 2011

Some ice blog readers have asked about the evidence that climate change is responsible for the increase in extreme weather events as discussed in the last post. This is something which is discussed a lot both by scientists and the general public. After all, it’s hard to find a more talked-about subject than the weather. Just this weekend, the Potsdam Institute for Climate Impact Research has just published a study in the journal Nature Climate Change on this very topic. The scientists say the last decade was a record in terms of extreme weather and that the increase was “very likely” caused by human-made global warming. They say there is now strong evidence for linking heatwaves and extreme rainfall to the human influence on climate. The evidence is less conclusive for other types of extreme weather like storms, but the scientists say observed trends and basic physics suggest it is plausible to expect an increase there too.

The study looks at extreme weather across the globe, including record rainfall events in Japan, record drought in the Chinese Yangtse basin, the hottest ever summer in western Russia (2010) and numerous extreme weather events in the USA.

The study is based on physics, analysis of statistics and computer simulations. The scientists say basic physics make it likely that a warming of the atmosphere will lead to more extremes. For instance warm air can hold more moisture until it suddenly falls as heavy rain. The statistics show clear trends in temperature and precipitation data. Last but not least, complex computer models confirm the link between warming and record temperatures and rainfall. Now that’s a fair bit of evidence to be going on with, don’t you think?