Climate scientists point finger at coal
In a just published paper, Andrew Weaver and Neil Swart emphasize the damage that coal (and unconventional gas) contribute to climate change (in addition to other environmental damage such as destruction of Boreal forest, mountain-top removal.)
They estimated the amount of greenhouse gas emissions from the Alberta tar sands. Here are some selected quotes from the Commentary (emphasis mine):
"If the entire Alberta oil-sand resource (that is, oil-in-place) were to be used, the associated carbon dioxide emissions would induce a global mean temperature change of roughly 0.36 °C"
"However, considering only the economically viable reserve of 170 billion barrels reduces this potential for warming by about tenfold (to 0.02– 0.05 °C)"
"Additional emissions resulting from natural gas, diesel and electricity use during bitumen extraction, upgrading and refining have not been included here, but could increase these numbers."
"Coal resources have the largest potential for global carbon emissions (79% of the total), followed by unconventional gas (15%) and only then the unconventional oil of which the Alberta oil sands form a part (3%)."
"If North American and international policymakers wish to limit global warming to less than 2 °C they will clearly need to put in place measures that ensure a rapid transition of global energy systems to non-greenhouse-gas-emitting sources, while avoiding commitments to new infrastructure supporting dependence on fossil fuels."
Commitments to new infrastructure include building new pipelines and new coal and gas based power generation plants.
Unfortunately, recent science does not consider a limit of 2 °C as safe. The Copenhagen accord recognized that 1.5 °C is a safer limit and recently climate scientists have said that 1 °C should be the limit.
According to their paper, proven reserves of coal could contribute about 0.92 °C, oil about 0.24 °C and gas 0.16 °C.
The really scarey number in the report is that if we use the total resource base of all fossil fuels we have the potential of raising global temperatures by over 9.46 °C.