"Mark Engler" - Dramatizing Obama's Climate Dilemma

http://www.commondreams.org/view/2011/08/26-6
President Obama now has a clear choice on climate change. Major energy corporations are seeking to build a 1700-mile oil pipeline from Canada’s tar sands to refineries in Texas. The Keystone XL Pipeline would itself carry social and environmental costs: cutting through fragile ecosystems, creating risk of spills, and negatively affecting indigenous communities. But, most significantly, it would be a boon to efforts to exploit the tar sands.
The Canadian tar sands are a particularly dirty source of fossil fuels that could produce egregious carbon emissions. As Elizabeth Kolbert reported at the New Yorker:
[B]ecause tar-sands oil is so heavy, it has to be very heavily processed, which requires tremendous amounts of energy, usually in the form of natural gas. It’s been estimated that, on what’s known as a well-to-tank basis, tar-sands oil is responsible for eighty percent more greenhouse-gas emissions than ordinary crude.
