The [Canadian/Albertan] oilsands contribute less than 0.15% of global GHG emissions, a number that has been called “a rounding error”. Even Andrew Weaver, a Green Party MLA has called it “almost undetectable”. The head of the IEA Fatih Birol also called oilsands GHG emissions “not peanuts, but fractions of peanuts”
Elsewhere though, among many examples, Pembina: Climate Impacts:
Average greenhouse gas emissions for oilsands extraction and upgrading are estimated to be 3.2 to 4.5 times as intensive per barrel as for conventional crude oil produced in Canada or the United States.
These are not necessarily inconsistent, but the underlying inquiry that both seem to be driving at is whether the Albertan oil sands are bad for the global environment because they emit a lot of greenhouse gasses.
So perhaps the question could be rephrased as: Does oil extraction contribute to greenhouse gasses worldwide? If so, is Alberta a significant contributor?