FILE - In this April 15, 1935 file photo, a dust cloud approaches a ranch in Boise City, Okla. The Oklahoma and Texas panhandles, the geographic center of the 1930s Dust Bowl, are hoping for an uptick in tourism following a two-part television series about what many call the nation’s worst man-made disaster. PBS’ series on “The Dust Bowl” concluded Monday, Nov. 19, 2012. (AP Photo, File)