As with California's other climate action efforts, this one could provide a roadmap for other states or for federal regulation, which the industry will likely fight.

California's dairy industry has fought most forms of pollution regulation, but now faces methane reduction requirements under a new law. Credit: Getty Images
Despite heavy pushback from the state's livestock producers, California Gov. Jerry Brown last month signed a law aimed at cutting methane emissions from cattle operations, the largest source of heat-trapping methane in the country's biggest dairy-producing state.
