ClimateBiz: The Environmental Defense Fund will sue the U.S. Environmental Protection Agency over outdated methane emissions standards for the country’s landfills. Methane is a greenhouse gas 21 times more potent than carbon dioxide and contributes to smog and climate change. The methane generated by decomposing solid waste in landfills is the second largest source of human-caused methane in the U.S. The gas, also produced in abundance on the nation’s dairy farms, has gained popularity in …