Speaking of Hurricane Sandy, I like this analogy:
On Oct. 29, Foley thumbed thusly: “Would this kind of storm happen without climate change? Yes. Fueled by many factors. Is storm stronger because of climate change? Yes.” Eric Pooley, senior vice president of the Environmental Defense Fund (and former deputy editor of Bloomberg Businessweek), offers a baseball analogy: “We can’t say that steroids caused any one home run by Barry Bonds, but steroids sure helped him hit more and hit them farther. Now we have weather on steroids.”
This makes the same point I made yesterday when I wrote about loaded climate dice– you can evaluate the randomness and variation of events by looking at many of them.
Just as we can not definitively tell from a single toss whether the dice is loaded or from a single home run whether Bonds was juiced, we can tell from the aggregate whether the extreme results fit any sort of normal variation or whether they are so unexpected that other factors must be involved.
So yes, Sandy could have happened without climate change. But the odds are so low as to be almost unimaginable.
But climate change tips the scales, making an almost impossible event not only possible but likely.