The Obama administration is planning several actions this summer to rein in greenhouse-gas emissions from wide swaths of the U.S. economy, including trucks, airplanes, oil and natural-gas operations and power plants, kicking into high gear an ambitious climate agenda that is a top legacy item for the president. The Environmental Protection Agency is expected to announce as soon as this week draft rules to cut carbon emissions from big trucks, and separate plans to regulate carbon emissions from airlines, according to people familiar with the proposals. In the coming weeks, the EPA is expected to propose rules cutting emissions of methane—a potent greenhouse gas—from oil and natural-gas operations. And in August, the agency will complete a suite of three regulations cutting carbon from the nation’s power plants, the centerpiece of President Barack Obama’s climate-change agenda. The regulations represent the biggest climate push by the Obama administration since 2009, when […]