Yale Environment 360: Gasoline and diesel refined from Canadian oil sands have a significantly larger carbon footprint and climate impact than fuels from conventional crude sources, according to an analysis by the U.S. Department of Energy's Argonne National Laboratory. Oil sands-derived fuels will release on average 20 percent more carbon into the atmosphere over their lifetime and possibly up to 24 percent more depending on how they are extracted and refined, the study says. Methane emissions from tailing ponds...