Michael Lemonick, a veteran science journalist, has an intriguing op-ed in today's LA Times. He argues that the severe weather/climate change attribution debate is too simplistic and unhelpfully framed around the wrong question. Here's a better way to think about this issue, he suggests:
An obese, middle-aged man is running to catch a bus. Suddenly, he clutches his chest, falls to the ground and dies of a massive heart attack. It turns out that he's a smoker and a diabetic, has high blood pressure, eats a diet high in saturated fat and low in leafy green vegetables, pours salt on everything, drinks too much beer, avoids exercise at all costs and has a father, grandfather and two uncles who also died young of heart attacks. So what killed him? Most people are savvy enough about health risks to know this is a trick question. You can't pick out a single cause. His choices and his genes all contributed to the heart attack "” but you can say with confidence that the more risk factors that pile up, the more likely it is to end badly. Somehow, though, people think that it makes sense to ask whether a given extreme weather event "” a devastating heat wave or a punishing drought or a deadly torrential rainstorm "” is caused by climate change. That's a trick question too. Scientists know that the increasing load of greenhouse gases we're pumping into the atmosphere doesn't "cause" extreme weather. But it does raise the odds, just as a diet of triple bacon cheeseburgers raises the odds of heart disease.
This sounds reasonable to me. The problem I have with the severe weather/climate debate is that all those other contributing factors Lemonick mentions largely get ignored, so that the global warming angle can remain paramount. For example, when we hear about the imminent "dust-bowl-ification" of the American Southwest or Australia, the discussion does not include the obvious risk of city-building in arid, marginal landscapes, and the kinds of policies in place that put populations there increasingly vulnerable to wildfires, extended droughts, etc. This is why I think global warming needs to be folded into a larger debate about sustainability. Because if we don't change our patterns of land use and development, reducing greenhouses gases isn't going to be enough to save cities like Los Angeles, Miami, or Phoenix. UPDATE: In the comments, Roger Pielke Jr. mentions something he wrote with Daniel Sarewitz in The New Republic in the early 2000s:
Prescribing emissions reductions to forestall the future effects of disasters is like telling someone who is sedentary, obese, and alcoholic that the best way to improve his health is to wear a seat belt.
UPDATE: Some context from Andy Revkin.