This is a more detailed run-up to the Lovelock disaster. One third of the world in drought severe enough to stop agriculture, mostly affecting areas already drought prone, such as the US heartland, thought they seem more focused on the third world. I still haven't found the original publication, but this seems to be a very newly released result. Further, note that the areas affected are the ones where the "bio-fuel revolution" hopes to grow its crops.
The Century of Drought