BY many measurements, this summer’s drought is one for the record books. But so was last year’s drought in the South Central states. And it has been only a decade since an extreme five-year drought hit the American West. Widespread annual droughts, once a rare calamity, have become more frequent and are set to become the “new normal.” http://www.nytimes.com/2012/08/12/opinion/sunday/extreme-weather-and-drought-are-here-to-stay.html?_r=2&hp