Climate Central: The Canadian tar sands, or oil sands, are much more carbon-laden than most other fossil fuels produced in North America, and their possible outsized impact on the climate is one of the primary reasons the proposed Keystone XLPipeline, which would carry tar sands oil to Texas refineries, is so controversial.
Despite long odds as oil prices continue their dip below $50 per barrel, commercial tar sands mining is coming for the first time to the U.S., where an Alberta company called U.S. Oil Sands...