Historically the Great Plains have been very dry. Well, pre-historically, from a European colonization perspective. There is a history of mega-droughts. If Euro

Historically the Great Plains have been very dry. Well, pre-historically, from a European colonization perspective. There is a history of mega-droughts. If Europeans had arrived in the midst of the thirty-year drought in the 1700's the settlement of the West would have been quite different. So independently of the accuracy of climate models--and the hiatus is a real, non-cherry-picked feature of the Hadcrut data, which was everyone's gold standard until the hiatus showed up in it (http://www.tjradcliffe.com/?p=1460)--there http://www.tjradcliffe.com/?p=1460)--there is very good reason to be concerned about the Great Plains returning to what amounts to historical conditions. This is the general case for policy responses to AGW: climate models don't have to be very accurate (which is good, because they aren't) to justify a modest investment in climate robustness, because our economic systems are finely tuned for the modern climate and we know it isn't going to last. The things that someone who wasn't insane would to to reduce GHG emissions--building nuclear power stations, regulating thermal coal into oblivion, shifting taxes from incomes to carbon emissions, investing in solar and storage--are all things that also either increase economic robustness against climate variations or have other economic benefits (you'd have to be some kind of wealth-hating socialist to want to tax incomes instead of carbon emissions, since incomes are good and carbon emissions are bad, and an externality besides.)