Try not to faint from shock. The controversial Keystone XL pipeline, which would carry Canadian oil through the US, will make climate change worse. It will boost global emissions of carbon dioxide by up to 110 million tonnes per year. The finding will step up the pressure on US president Barack Obama to stop the pipeline being built.

That extra CO₂ is not a huge amount on a global scale. “But it is a step in the wrong direction,” says Jerry Schnoor of the University of Iowa in Iowa City, who was not involved in the new analysis. “It is an investment that will lock us into an untenable environmental situation. It’s a pipeline to nowhere, economically speaking.”

Keystone XL, proposed by the Canadian energy company TransCanada, is intended to run from Alberta, Canada, to Steel City, Nebraska. There it would link to existing pipes, to carry oil from Canada’s tar sands to refineries on the US’s Gulf of Mexico coast.

It has proved to be enormously controversial. Its supporters argue it will boost the economy, while environmentalists say the toxic oil could be spilled and that it encourages the use of tar sands, which produce more greenhouse gases than normal oil.

 

Extra carbon dioxide

Barack Obama must decide whether to allow its construction. On 25 June 2013, he mentioned Keystone XL in a speech about climate change. Obama said that the pipeline could be built only if it “does not significantly exacerbate the problem of carbon pollution“. Now it seems it will.

The new study comes from Peter Erickson and Michael Lazarus of the Stockholm Environment Institute in Seattle, Washington. They estimated how much building Keystone XL would affect oil prices. For every barrel of extra oil obtained from tar sands as a result of the pipeline, global oil consumption would increase by 0.6 barrels, because the extra oil would lower oil prices and encourage people to use more.

“The maths works out. The model is simple and straightforward,” says Nico Bauer of the Potsdam Institute for Climate Impact Research in Germany.

It makes sense, says Schnoor. “Common sense holds that the Keystone XL pipeline will increase supply from the Alberta oil sands region,” he says. That’s because the bottleneck in the whole system is getting the oil to the refineries. “Canada has much more oil sands that could be brought into production if they had infrastructure to get it refined and to market.”

Supply and demand

Yet Erickson and Lazarus’s study flies in the face of the official assessment by the US Department of State, the final version of which was published in January this year. The DoS argued that Alberta’s oil sands would be exploited, and their carbon released, regardless of whether or not Keystone is built.

“Their sum conclusion is that Keystone doesn’t unlock the oil sands at all,” says Erickson. “They just wave their hands and say zero. You end up scratching your head.”

The US Environmental Protection Agency slammed several components of the DoS study in April last year, when it was still a draft. The EPA said the DoS had not accounted for the market effects of increased oil supply through Keystone XL. “We note that the discussion… regarding energy markets, while informative, is not based on an updated energy-economic modelling effort,” the EPA wrote.

Erickson and Lazarus’s analysis confirms the EPA’s suspicions. They say the DoS study failed to account for the effect of a flood of tar sands oil hitting the market through Keystone XL. Essentially, the DoS ignored the fundamental economic principle of supply and demand. When Erickson and Lazarus took this into account, it turned out Keystone XL will be about four times more carbon intensive than the DoS estimate.

It’s not clear the emissions would be quite as big as that, says Deepak Rajagopal of the University of California, Los Angeles. “If this pipeline was not built, the materials and energy and labour would [be] allocated to some other project,” he says. But he says that should not affect the overall conclusion.

Time to cut emissions

Obama is trying to cut the US’s greenhouse gas emissions, for instance clamping down on emissions from power stations. Erickson says not building Keystone offers instant emissions cuts, of a magnitude that the government is retooling entire industries over many years to achieve elsewhere. “[It’s] a carbon saving policy that the US has at its fingertips,” says Erickson.

“The combined effects of the standards for industrial boilers and cement kilns is just 20 to 60 million tonnes of CO₂ a year,” Erickson says. “Even new power plants to be built by 2020 are expected to save 160 to 575 million tonnes annually.”

“When do we begin to stop?” asks Schnoor. “If not now, when? If one accepts that climate change is a very serious problem, and I do, one concludes that investing in infrastructure that will last 50 years or more is simply not prudent.

Journal reference: Nature Climate Change, DOI: 10.1038/nclimate2335