Due to ongoing drought conditions, the USDA has just declared more than 1,000 counties natural disaster areas, making it the largest natural disaster in America ever. Not good news at any time but especially disheartening for conventional thinkers who've yet to grapple with an ominous report out of the University of Minnesota that predicts world food demand will double by 2050. Ever optimistic, or perhaps unphased by conventional wisdom, the local food movement offers a common sense solution to this coming agricultural crisis: diversify farms and bring them closer to the people. Urban farms (and a government promotion of them) are in no way a new idea. By the height of the second world war, Americans were "sowing the seeds of victory," producing a majority of their own fruits and vegetables on a local level. These farms come in many forms, from abandoned city lots to sprawling warehouse rooftops. Take this -- the largest rooftop farm in the world -- for example. The Brooklyn Grange is a shining example of sustainable agriculture, and it exists atop a 40,000 square ft facility in the nation's biggest metropolis. Imagine if these cought on. What better way to put the de-industrialized part of America back to work while taking some of the burden off of hard-hit agribussinesses thousands of miles away?