National Public Radio: Photographer Matt Black grew up in California's Central Valley. He has dedicated his life to documenting the area's small towns and farmers. Last year, he says he realized what had been a mild drought was now severe. It had simply stopped raining. "It was kind of a daily surreal thing to walk outside," Black says. Last month, Governor Jerry Brown announced the first mandatory water restrictions in the state's history, as California endures its fourth year of drought. The Central Valley makes...