New York Times: Recent events highlight concerns about the risks to global food security posed by changing patterns of extreme weather affecting the worlds breadbasket regions such as the American Midwest, South Americas southern cone, the Black Sea and the Yangtze River valley. In 2012, the worst drought to hit the U.S. Midwest in half a century sent international maize and soybean prices to record levels. In 2011, wheat prices nearly doubled after an unprecedented heat wave devastated the Russian harvest....