A pair of climate scientists has examined the thorny question of whether the cluster of recent extreme weather events has been caused by increasing global temperatures. Their answer? No proof, but it seems likely.
Dim Coumou and Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research say that the jury is still out on how – or whether – global warming might influence a specific extreme weather event such as the 2003 European heatwave.
"That such outliers are mere freak events, so called black swans, is a possibility," they write. "However, the recent clustering of outliers makes this seem highly unlikely."....
....That same study, however, also noted that "we may be on the cusp of a period in which the probability of such events increases rapidly, due primarily to the influence of projected increases in greenhouse gas concentrations."
It's all about probability, not certainty, say Coumou and Rahmstorf. As tempting as it may be to assign specific weather events to climate disruption, the best that the current state of climate science can do is to assign probabilities. That said, as temperatures rise, the probabilities begin to lean towards clusters of extreme weather events such as the world is now experiencing, they suggest.
"If a loaded dice rolls a six," they write, "we cannot say that this particular outcome was due to the manipulation – the question is ill-posed. What we can say is that the number of sixes rolled is greater with the loaded dice (perhaps even much greater). Likewise, the odds for certain types of weather extremes increase in a warming climate (perhaps very much so). Attribution is not a 'yes or no' issue as the media might prefer, it is an issue of probability."
Speaking of probability, Coumou and Rahmstorf cite a 2004 study which concluded that "human influence has at least doubled" the chance of a European heatwave as severe as 2003's.
Coumou and Rahmstorf do cite one bit of good news: a 2010 study which concluded that "it remains uncertain whether past changes in tropical cyclone activity have exceeded the variability expected from natural causes."
That is, of course, if uncertainty about the effects of global warming gives you comfort.
Click source to read FULL report from Rik Myslewski