On 9 May, the government of Alberta released a study into the extra carbon emitted by crude produced using oil sands instead of more conventional sources. The study, by a unit of California based Jacobs Engineering Group, found that emissions from oil-sand crude are just 12% higher than from regular crude. But the report was not just about the science. It also sent a political signal to Europe: Canada’s fight over oil sands is not done yet. As part of its ambitious efforts to cut carbon emissions, the EU has proposed classifying crude produced from oil sands, or “tar sands”, as environmentalists and others call them, as much dirtier than other fuels. A 2011 study for the EU by Stanford University academic Adam Brandt found that oil-sand crude was as much as 22% more carbon-intensive. Canada, whose oil sands have helped it become an energy power, fears such a ruling could imperil a resource it estimates will add more than C$3 trillion to its economy over the next 25 years. Which is why Ottawa has waged a concerted lobbying campaign against Brussels’ proposal over the past three years, reports Reuters.