California Gov. Gray Davis (D) signed trailblazing legislation yesterday that will require automobile manufacturers to reduce the amount of greenhouse-gas emissions coming from the tailpipes of passenger vehicles in the state. Under the terms of the new law, the California Air Resources Board has until 2005 to set “maximum” but “economically feasible” emissions standards for gases that contribute to climate change; new automobiles sold in the state must meet those standards by 2009. In signing the law, Davis said, “I would prefer to have Washington take the lead, but in the absence of that we have no choice but to do our part. … It is my hope that other states will do the same thing.” In fact, the law is likely to have nationwide ramifications, because California accounts for 10 percent of the national car market. The industry opposes the new law, and the Alliance of Automobile Manufacturers has announced plans to take California to court.