Tar Sands vs. Coal

The term “fossil fuels” is a very large umbrella. Coal, oil, and natural gas are the usual distinctions, but there’s also unconventional oil (such as the Alberta tar sands) and unconventional gas (such as shale gas from fracking). “Unconventional” means that the fuel is produced in a roundabout way that’s less efficient and takes more energy than regular fuel. For example, oil in northern Alberta is mixed with sand and tar that’s difficult to remove. As global supplies of conventional oil and gas decline, unconventional fuels are making up a growing segment of the petroleum market.

The different types of fossil fuels are present in different amounts in the ground. Also, for each unit of energy we get from burning them, they will release different amounts of carbon emissions. Given these variables, here’s an interesting question: how much global warming would each type of fuel cause if we burned every last bit of it?

A few weeks ago, a new study addressed this question in one of the world’s top scientific journals. Neil Swart, a Ph.D. student from the University of Victoria, as well as his supervisor Andrew Weaver, one of Canada’s top climate scientists, used existing data to quantify the warming potential for each kind of fossil fuel. Observations show the relationship between carbon emissions and temperature change to be approximately linear, so they didn’t need to use a climate model – a back-of-the-envelope calculation was sufficient. Also, since both of the authors are Canadian, they were particularly interested in how burning the Alberta tar sands would contribute to global warming.

Swart and Weaver calculated that, if we burned every last drop of the tar sands, the planet would warm by about 0.36°C. This is about half of the warming that’s been observed so far. If we only burned the parts of the tar sands proven to be economically viable, that number drops to 0.03°C. If we don’t expand drilling any further, and stick to the wells that already exist, the world would only warm by 0.01°C, which is virtually undetectable.

Conventional oil and natural gas would each cause similarly small amounts of warming, if the respective global supplies were burned completely. Unconventional natural gas would cause several times more warming – even though it’s cleaner-burning than coal and oil, there’s a lot of it in the ground.

The real game-changer, though, is coal. If we burned all the coal in the ground, the world would warm by a staggering 15°C. There’s a large uncertainty range around this number, though, because the linear relationship between carbon emissions and temperature change breaks down under super-high emission levels. The warming could be anywhere from 8°C to 25°C. In the context of previous climate changes, it’s hard to overemphasize just how dramatic a double-digit rise in average temperatures would be.

The main reason why the warming potential of coal is so high is because there’s so much of it. The Alberta tar sands are a huge resource base, but they’re tiny in comparison to global coal deposits. Also, coal is more polluting than any kind of oil: if you powered a lightbulb for one hour using coal, you would produce about 30% more CO2 emissions than if you ran it using conventional oil.

The tar sands are more polluting than regular oil, but exactly how much more is a very difficult question to answer. The end product that goes into your car at the gas station is essentially the same, but the refining process takes more energy. You can supply the extra energy in many different ways, though: if you use coal, tar sands become much more polluting than regular oil; if you use renewable energy that doesn’t emit carbon, tar sands are about the same. The authors didn’t include these extra emissions in their study, but they did discuss them in a supplementary document, which estimated that, in an average case, tar sands cause 17% more emissions than regular oil. Taking this into account, the tar sands would cause 0.42°C of warming if they were burned completely, rather than 0.36°C.

Therefore, headlines like “Canada’s oil sands: Not so dirty after all” are misleading. Canada’s oil sands are still very dirty. There just isn’t very much of them. If we decide to go ahead and burn all the tar sands because they only cause a little bit of warming, the same argument could be used for every individual coal plant across the world. Small numbers add up quickly.

The authors still don’t support expansion of the tar sands, or construction of pipelines like the Keystone XL. “While coal is the greatest threat to the climate globally,” Andrew Weaver writes, “the tarsands remain the largest source of greenhouse gas emission growth in Canada and are the single largest reason Canada is failing to meet its international climate commitments and failing to be a climate leader.” Nationally, tar sands are a major climate issue, because they enable our addiction to fossil fuels and create infrastructure that locks us into a future of dirty energy. Also, a myriad of other environmental and social problems are associated with the tar sands – health impacts on nearby First Nations communities, threats to iconic species such as the woodland caribou, and toxic chemicals being released into the air and water.

Tar sands are slightly preferable to coal, but clean energy is hugely preferable to both. In order to keep the climate crisis under control, we need to transition to a clean energy economy as soon as possible. From this viewpoint, further development of the tar sands is a step in the wrong direction.

The Tar Sands

Apologies for the few weeks of silence. Moving cities again, combined with the beginning of a new term, meant hardly any writing time! I should be back into a regular routine now, though. Enjoy.

In the 2008 presidential campaign, Barack Obama seemed serious about climate change action. He promised an 80% reduction in American greenhouse gas emissions by 2050: a target which, if reached, would go a long way in solving global warming. Therefore, when he won the election, citizens concerned about climate change cheered the world over. “We will restore science to its rightful place,” Obama said following his inauguration. “We will harness the sun and the winds and the soil to fuel our cars and run our factories…All this we can do. And all this we will do.”

This cheery picture of a renewable energy economy is about as far away as one can get from the energy source Obama is now considering supporting: tar sands. Concentrated in Western Canada, the tar sands are an unconventional, and very dirty, form of oil. They produce more carbon dioxide emissions per unit of energy than regular petroleum – in fact, if you take transport and refinery into account, they’re slightly worse than coal. If we aggressively develop the tar sands, we will have no hope of stabilizing climate change at a reasonable level.

The problems don’t end there. Extraction and refinement takes over an incredible amount of land that would otherwise serve as vital habitat for wildlife. Additionally, tar sands are loaded with toxic substances such as heavy metals, which are removed during the refinement process. These byproducts inevitably leach into the water system, endangering the health of nearby First Nations communities and the viability of entire ecosystems in the boreal forest.

In my opinion, this is Canada’s most shameful practice. A short-term spike in jobs will lead to centuries of social, environmental, and economic damage. Sadly, many of our politicians think this trade-off is acceptable.

Now, industry is hoping for an American partnership in tar sand development. The proposed Keystone XL Pipeline would run all the way from Alberta to Texas, so tar could be refined in the US. Imagine the habitat destruction and pollution required to construct this pipeline. Imagine the consequences of a leak in the pipe. And imagine how much more of the tar sands will get dug up and burned if there is a demand from the US.

Luckily, this pipeline requires special permission from the president in order to be built. There is no deadlock in Congress to worry about; no concessions to make for the Tea Party. It’s all down to Obama. Will he keep his campaign promises?

How could someone promise to “restore science to its rightful place” while making decisions that every line of science predicts will endanger our future? How could someone make specific goals and targets, then turn around and take actions that guarantee these goals will fail? If the Keystone XL Pipeline is approved, it won’t be by the Obama we knew in 2008.

350.org, a nonprofit climate change action group, is coordinating a movement pressuring Obama to reject the pipeline. It includes typical lobbying efforts, including a petition signed by over 600 000 people, but is centered on a two week stretch of civil disobedience. Waves of volunteers formed a peaceful sit-in on White House property, and were willing to get arrested to draw attention to the issue. As of the sit-in’s conclusion on September 3rd, a total of 1,252 people had been arrested, including top climate scientist James Hansen, environmental journalist Bill McKibben, and author Naomi Klein.

Others condemned the pipeline at more of a distance. Recently, nine Nobel Peace Prize Laureates, including the Dalai Lama and Desmond Tutu, wrote to Obama, pleading with him to reject the proposal. Youth leaders from the PowerShift conferences threw in their support. Unsurprisingly, Al Gore denounced the pipeline, calling it an “enormous mistake”.

Is civil disobedience the answer? Will it build up the movement, or polarize it? If governments don’t listen to letters, why would they pay attention to protests? But if they don’t listen to this, why should we trust them at all?