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The 350-foot U.S. Army Corps of Engineers' Dredge Hurley works to clear a navigation channel on the Mississippi River on Monday, Aug. 20, 2012 near Memphis, Tenn. (AP Photo/Adrian Sainz)

U.S. drought crisis

Triple-digit temperatures and weeks without rain withered and destroyed many crops in the Midwest, sending commodity soybean and grain prices soaring in 2012.