Ethanol test for Obama on climate change, science

President Barack Obama's commitment to take on climate change and put science over politics is about to be tested as his administration faces a politically sensitive question about the widespread use of ethanol: Does it help or hurt the fight against global warming? The Environmental Protection Agency is close to proposing ethanol standards. But two years ago, when Congress ordered a huge increase in ethanol use, lawmakers also told the agency to show that ethanol would produce less pollution linked to global warming than would gasoline. So how will the EPA define greenhouse gas emissions from ethanol production and use? Given the political clout of farm interests, will the science conflict with the politics? Environmentalists, citing various studies and scientific papers, say the agency must factor in more than just the direct, heat-trapping pollution from ethanol and its production. They also point to "indirect" impacts on global warming from worldwide changes in land use, including climate-threatening deforestation, as land is cleared to plant corn or other ethanol crops. Ethanol manufacturers and agriculture interests contend the fallout from potential land use changes in the future, especially those outside the United States, have not been adequately proven or even quantified, and should not count when the EPA calculates ethanol's climate impact...WPost