Throughout this year I have posted a number of blogs on the record-breaking  extreme weather events of recent years, particularly 2010. Events ranged from unprecedented blizzards  on the U.S. East Coast to the cataclysmic Russian heat wave and flooding  in Pakistan. The key message I’ve tried to communicate is that, rather than debating whether these particular events are being caused by climate change – an interesting academic question that is unanswerable on a practical level – we should learn  from these events about our individual and societal vulnerabilities and the real costs of climate change.
In an op-ed in The New York Times, Jack Hedin, a Minnesota farmer, offers an excellent example of the type of practical learning I’m talking about:
“The past four years of heavy rains and flash flooding here in southern Minnesota have left me worried about the future of agriculture in America’s grain belt. For some time computer models of climate change have been predicting just these kinds of weather patterns, but seeing them unfold on our farm has been harrowing nonetheless.”
Mr. Hedin’s family has farmed the soils of southern Minnesota since the late 19th century. Today he runs a small farm in Rushville, where an onslaught of extreme weather events over several years forced him to retreat to higher ground. This is an example of forced adaptation where abandonment was the best choice. But even in the new location, his farm lost $100,000 worth of crops to excessive soil moisture this summer.
Notice that Hedin doesn’t waste time worrying about whether particular weather events were caused by human-induced climate change:
“The weather in our area has become demonstrably more hostile to agriculture, and all signs are that this trend will continue. Minnesota’s state climatologist, Jim Zandlo, has concluded that no fewer than three “thousand-year rains” have occurred in the past seven years in our part of the state. And a University of Minnesota meteorologist, Mark Seeley, has found that summer storms in the region over the past two decades have been more intense and more geographically focused than at any time on record.”
Climate scientists know the climate is changing , that many mid-latitude locations are becoming wetter as a result (see figure below), and that we can expect that trend to continue. What does it matter whether a particular storm on a particular day in a particular year was caused by human intervention with the climate system? After all, it isn’t one particular event that has Mr. Hedin worried about the future of farming in America’s grain belt; it’s the preponderance of evidence that the climate is already shifting and the common sense realization that farming is getting harder because of that shift.
Please read Jack Hedin’s op-ed  in The New York Times. He has the right idea about learning from extreme weather events.
Jay Gulledge is Senior Scientist and Director of the Science and Impacts Program