There are no shortage of reasons why the Keystone XL pipeline has become such a hot button issue for environmentalists. Many worry about the risks the project could pose to the Ogallala aquifer in Nebraska, where the pipeline was originally designed to pass. Indeed, when President Obama rejected Keystone XL in January, his stated concern was the potential threat to local water supplies.
But every pipeline—and there are millions of miles of them running through the U.S.—carries a risk of a spill. What makes Keystone XL special is its connection to the Albertan oil sands. Environmentalists oppose the oil sands in part because mining and processing the bitumen can be a messy process—as I saw when I visited the oil sands in September 2010. (Oil companies argue that the effects are temporary, and that the land can be restored over time.) But the real issue here is all the carbon that would be released into the atmosphere if all the crude in the oil sands is burned. The NASA climatologist James Hansen put it bluntly (PDF): according to his calculations, the entire oil sands reserve contained enough carbon to raise the atmospheric concentration of CO2 by 200 ppm. If all of that oil were tapped, it would be “game over” for the climate.
Building the Keystone XL pipeline, which would carry over 800,000 barrels a day of oil sands crude, would bring the world that much closer to fully exploiting the oil sands—and that has been reason enough for greens to put all their energy into opposing the pipeline. But a new study in Nature Climate Change, a pair of Canadian researchers crunch the numbers on the oil sands, and find that its potential impact on the climate—while significant—may not be as catastrophic as it seems.
Andrew Weaver and Neil Swart of the University of Victoria in Canada first modelled the warming impact of burning the 170 or so billion barrels of crude believed to be technically recoverable from the Albertan oil sands. They found that burning all of that carbon would produce just 0.02 to 0.05 C of warming. As David Biello of Scientific American points out, global warming to date is 15 times greater than that.
Should energy companies figure out a way to mine and burn all 1.8 trillion barrels of oil believed to be in the oil sands, the warming would obviously be greater—but not that much greater. Weaver and Swart estimate all that oil would lead to an additional 0.36 C of warming. Given that many scientists believe we need to prevent 2 C of warming above pre-industrial levels to avoid catastrophic effects—and that we’re already a little less than halfway there—the oil sands seem to represent an important but not decisive front in the climate battle.
Another way to look at the question is to compare the potential warming potential of the oil sands to some of then other major sources of carbon. As it turns out coal—which Hansen himself has called the “enemy of the human race”—accounts for 79% of the total potential for global carbon emissions. Total unconventional oil reserves account for just 3% of the carbon potential, and the oil sands are just a small part of that. It’s coal—more than any other single source—that will decide the game on climate change.
Of course, environmentalists recognize that fact. Fighting coal—whether through conventional air pollution regulations or through climate action—is a top priority for major green groups, as the Sierra Club’s multi-million dollar Beyond Coal campaign shows. And as Weaver and Swart write in their article, without an aggressive climate policy, our chances of preventing significant warming are almost nil:
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 nongreenhouse-gas-emitting sources, while avoiding commitments to new infrastructure supporting dependence on fossil fuels.
Some real talk here: the battle against the Keystone XL pipeline is primarily a political one. Greens have seized on the pipeline not because the construction of Keystone itself would be so disastrous, or even that the oil sands as a whole are decisive for the global climate, but because the project is a clear symbol that can be overtly opposed. It helps as well that the decision on Keystone XL fell to President Obama, who might actually listen to his environmental base—unlike the conservative-dominated Congress. And the public always tends to be suspicious of newer development, which might make it easier to lead a campaign against oil sands than coal, which we’ve lived with for more than a century.
The reality is that the Keystone battle is being fought in part because the larger climate battle—in the U.S.—has become almost totally stalled. The Albertan oil sands are worth trillions of dollars, and it’s almost impossible for me to imagine that the Canadian government won’t find a way to tap that reserve—even if Keystone remains blocked. No government leaves that much money in the ground. The only way I can see that happening is if the U.S. and other governments adopt climate policies that really do make the oil sands uneconomical—and if alternative technologies arise that can replace oil in the global economy. Neither outcome seems likely to happen any time soon. The good news from the Nature Climate Change paper is that, should environmentalists lose their battle, the consequences might not be quite as bad as they’ve made it out to be.