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Canada and Climate: From Leader to Threat

Henry Shue on why burning through our limited carbon budget is going to cost us dearly.

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14 March, 2013
By: Henry Shue
Senior Research Fellow, Centre for International Studies, Department of Politics and International Relations, University of Oxford

A quarter of a century ago, Canada was a world leader in tackling the threat to the earth’s climate.  The World Conference on the Changing Atmosphere held in June of 1998, was hosted in Toronto by a far-sighted Canadian government. The conference was an early ringer of the alarm bell on global climate change, calling for 20% reductions below 1988 levels in greenhouse gas (GHG) emissions by 2005, and urging the adoption of an “international framework convention” to control GHG emissions, which led in 1992 to the United Nations Framework Convention on Climate Change (UNFCCC).  Canada once promised to lead the world in finding a solution to climate change, but now, it is increasingly part of the problem.  Global GHG emissions are soaring far above 1988 levels – they have increased every year except during the global recession. Climate changes are occurring all around us as global temperatures rise higher than any other time in at least 4,000 years.

Canada failed to meet even the cautious emissions reductions targets it pledged under the Kyoto Protocol and, far more ominously, now seems to be putting an excessive percentage of its national economic eggs in one basket: heavy oil extraction in the Alberta tar sands.

Debates over the policy of heavy, long-term reliance on tar sands oil have so far largely missed the most critical point when it comes to the climatic impacts, because they have failed to take our improved understanding of the dynamics of climate change into account.  It is true that Alberta’s GHG emissions from “expanding oil-sand production are Canada’s fastest-growing emissions source,” but prior to Swart and Weaver’s careful and conservative analysis in Nature Climate Change, attention was largely focused only these GHG emissions – those that result from extracting, shipping, and refining the tar sands oil. What matters incomparably more are the GHG emissions that would result from actually burning that extracted oil. 

An example of the all-too-typical analysis that ignores this point is the embarrassingly poor supplementary environmental impact statement concerning the proposed Keystone XL pipeline, recently drafted by the U.S. Department of State. The draft focuses relentlessly on peripheral issues and never even approaches the heart of the matter, which is that the purpose of extracting, shipping, and refining the oil is to burn it. There is no consideration of the predictable consequences for the climate of actually using the oil from the tar sands.

Canada failed to meet even the cautious emissions reductions targets it pledged under the Kyoto Protocol

The State Department seems blind to the fact that humanity’s global emissions budget is limited and cumulative.1 Future consumers will add a certain additional amount of carbon dioxide to that which has already accumulated in the earth’s atmosphere by burning fossil fuels, so a corresponding amount of additional temperature rise on the surface of our planet can be expected.  If we add still more carbon dioxide to that growth, we can expect an even greater consequent rise in surface temperature (and an intensification of all the other elements of climate change).  And so on.  In short, the single factor that correlates most strongly with rises in surface temperature is the total accumulation of carbon dioxide in the atmosphere, measured from the time when humans began to emit more carbon dioxide than could be re-cycled via organic processes, so from approximately the late 18th century onward, when the fossil-fuel-driven Industrial Revolution began to gather momentum.

The reason why cumulative carbon in the atmosphere is the critical factor is because of the atmospheric residence time of carbon dioxide molecules, which is extraordinarily long: the average molecule remains in the atmosphere for centuries and a major percentage remain for a millennium.2 Additions to the atmospheric concentration tend to be long-term net additions because the departure of carbon dioxide from the atmosphere occurs so many times more slowly than its entrance.

Accordingly, for any given total accumulation of carbon dioxide in the atmosphere, there will most likely be a temperature rise on the surface where we, and our crops, are.  Specific numbers will be refined as scientific investigation goes forward, but there is an impressive international consensus of scientific opinion that, for example, for there to be a decent chance at restricting temperature rise beyond the pre-Industrial-Revolution to 2° C, the total atmospheric accumulation of carbon dioxide must be limited to around 1 trillion tons.  Initially that may sound like a comfortingly large number, but it isn’t.  The best estimates find, for example, that as of March 7th 2013, our atmosphere had accumulated 568 billion tons (568 Gt) of carbon dioxide. Another seemingly comforting fact is that this accumulation of the first half trillion tons has taken place over about the last 250 years.  But this fact is only comforting if one ignores that annual rates of carbon emissions have kept rising across those decades to the point that now, if the rates of emissions increases that have occurred over the past 20 years continue into the future, the remaining half trillion tons will reach the atmosphere in far fewer than 250 years – well under 40, in fact – so during the life-time of our own children. 

The point here, however, is not specific numbers, but the general concept of the cumulative budget of atmospheric carbon; a powerful, but so far neglected, tool in the assessment of energy policy.  What can it tell us about the value of Alberta’s tar sands oil? Swart and Weaver at the University of Victoria use the estimate of oil-in-place in the tar sands made by the Energy Resources Conservation Board in 2011: 1.8 trillion barrels.3  The currently economically viable ‘proven reserve’ in the oil sands is estimated at the much smaller quantity of 170 billion barrels, but no one believes that in the absence of sustained opposition, the exploitation will stop with today’s ‘proven reserve’.  The governments of the world’s countries, negotiating in Copenhagen in December 2009 and Cancun in December 2010, adopted on behalf of humanity the goal of preventing the rise in average global surface temperature from exceeding 2° C.  Swart and Weaver calculate that if the 1.8 trillion barrels of oil-in-place in Alberta were burned as fuel, the carbon dioxide released “would induce a global mean temperature change of roughly 0.36° C.”4  As the carbon dioxide from burning the tar-sands oil used up another chunk of the remaining budget of cumulative atmospheric carbon dioxide, we would move 0.36° C closer to a global temperature rise of 2° C.

global warming

A 0.36° C of rise in average global temperature may not seem too worrisome to those unfamiliar with climate change.  For perspective, however, consider that it is, first, almost exactly half of the 0.76° C increase already observed over the past 100 years (so we have only 1.24° C left to go under the limit chosen for our safety) from the burning of all fuels and, second, it is slightly more than the 0.34° C increase to be expected from burning all the conventional oil on the planet.

It is overwhelmingly obvious from this data that we do not dare to burn all the fossil fuels that are available to be burned.  But what about the Alberta tar-sands oil in particular?  The best that can be said of this particular emissions source is that it contains less carbon than coal, and that the burning of all the oil potentially to be extracted from the tar sands would not, on its own, completely consume humanity’s remaining margin of safety.5 Fully exploiting Alberta’s tar sands would exhaust only 0.36° C of the 1.24° C of temperature rise possibly remaining under the limit of 2° C.6 But the burning of Alberta’s oil with current technology would intensify the threat of unsustainable climate change as much as would burning all of the conventional oil on earth. Canada’s current economic policy of exploiting the oil sands is therefore a significant addition to humanity’s peril.

Some of those who seek to portray opponents of the exploitation of Alberta’s oil sands as alarmists reference the May 2012 op-ed piece titled “Game Over for the Climate” in the New York Times by eminent climate scientist James Hansen. They misrepresent Hansen, suggesting that he wrote that the burning of the oil from the tar sands would, by itself, mean “game over for the climate”, when what he actually wrote was, “if Canada proceeds, and we do nothing, it will be game over for the climate” (emphasis added). Hansen then continued:

Canada’s tar sands … contain twice the amount of carbon dioxide emitted by global oil use in our entire history.  If we were to fully exploit this new oil source, and continue to burn our conventional oil, gas and coal supplies, concentrations of carbon dioxide in the atmosphere eventually would reach levels higher than in the Pliocene era, more than 2.5 million years ago, when sea level was at least 50 feet higher than it is now.

Although it would take quite a while for cumulative atmospheric carbon to reach Pliocene levels, and one can argue about how helpful it is to invoke that comparison right now, what Hansen says is completely correct – only an extraordinarily careless reader would fail to notice that he is saying that tar-sands oil is only part of the danger, which is, in fact the crucial point. Tar-sands oil is part of the danger for it makes the human situation significantly worse.  Canada has made valuable contributions to global welfare, but its exploitation of the tar-sands goes on the other side of the ledger.

We need the tar sands oil like we need a dagger in the back. This is perfectly clear from the careful, conservative calculations by Swart and Weaver cited in this essay.  If Alberta’s heavy oil were left in the sand where it does us no harm, as has been the case for millennia, we would still have more fossil fuel than we could possibly dare to burn with current technology.  Humanity does not need the tar-sands oil.  We already have more than enough to cause warming far beyond any temperature to which known forms of agriculture can adjust.  Spending US$13 billion on TransCanada’s proposed Keystone XL pipeline would therefore represent a large backward step.  Investments in infrastructure of that magnitude need to go into ‘green infrastructure’ that will hasten the day when the danger of exceeding the cumulative atmospheric carbon budget has disappeared, because we are no longer injecting carbon dioxide into the earth’s atmosphere.  The Keystone XL pipeline is the infrastructure of the day before yesterday, not of the de-carbonized tomorrow the world so urgently needs.

We need the tar sands oil like we need a dagger in the back

It is also unclear how long carbon reserves and the equities whose value rests on them can retain their current value as governments gradually come to appreciate that we are running a potentially devastating carbon budget deficit.  In 2011 the Carbon Tracker Initiative in London, which educates investors about the possible risks to their stock portfolios of climate change, released an increasingly influential report, entitled: Unburnable Carbon – Are the world’s financial markets carrying a carbon bubble? The report explores the possibility that if “only one fifth of the total reserves can be used to stay below 2° C warming,” the current value of the companies whose valuation depends on reserves of fossil fuels is greatly inflated.  The value of the companies and their stock is linked to the assumption that the gas, oil, and coal in the reserves they own will be extracted, sold, and burned.  But it is perfectly clear from the graphic above that only a fraction of total global carbon resources can in fact be burned without intolerable rises in temperature. The research, development, and dissemination of technologies that could change this calculus are nowhere in sight.

A final opposing argument that dissipates upon closer examination is that the addition to the world supply of oil of the heavy oil from Alberta can help to keep oil prices lower for consumers in the U.S. (good for North American manufacturing), and in emerging countries, (good for addressing inequality in global development).  This may be true, but lower prices actually risk reversing the limited progress that is being made in curbing global emissions.  Preventing dangerous climate change depends on discouraging the discharge of carbon dioxide by increasing the prices of fossil fuels according to their carbon content – carbon taxes, cap-and-dividend, cap-and-trade, etc.  Increasing the supply by unnecessarily exploiting new sources like the tar sands works directly against smart climate policy.  Prices for oil, gas, and coal need to go up – the sooner we reconcile ourselves to this, the better off we, and our children will be.  Consumers may be happy in the short-term and will likely support politicians who pander to them, but the welfare of future generations depends upon a rapid exit from reliance on fossil fuel and the prompt defeat of politicians who take only the short-term view.  Canada ought to turn away from the old carbon economy that endangers so many and profits so few, and return to leading the world on tackling climate change.

1  The conceptual point is lain out in a relatively accessible manner in Myles Allen, et al., “The Exit Strategy,” Nature Reports Climate Change, 3 (2009), 56-8, at 57.  The underlying research is reported in Malte Meinshausen, et al., “Greenhouse-Gas Emission Targets for Limiting Global Warming to 2º C,” Nature, 458 (2009), 1158-1162; and Myles Allen, et al., “Warming Caused by Cumulative Carbon Emissions Towards the Trillionth Tonne,” Nature, 458 (2009), 1163-1166.  A policy-relevant follow-up study is in Niel H.A. Bowerman, et al., “Cumulative Carbon Emissions, Emissions Floors and Short-Term Rates of Warming: Implications for Policy,” Philosophical Transactions of the Royal Society A, 369 (2011), 45-66; and for a more sophisticated discussion of the science than mine here, see R.T. Pierrehumbert, “Cumulative Carbon and Just Allocation of the Global Carbon Commons,” Chicago Journal of International Law, 13 (2013), 527-548.

2  David Archer and Victor Brovkin, “The Millennial Atmospheric Lifetime of Anthropogenic CO2,” Climatic Change, 90 (2008), 283.  The policy implications of carbon dioxide’s lengthy lifespan relative to other greenhouse gases are explored in H. Damon Matthews, Susan Solomon, and Raymond Pierrehumbert, “Cumulative Carbon as a Policy Framework for Achieving Climate Stabilization,” Philosophical Transactions of the Royal Society A, 370 (2012), 4365-4379.

3  Swart & Weaver, 134.

4  Ibid., 135.  These calculations assume a specific carbon budget, namely 1.5° C of temperature rise for each trillion metric tonnes of carbon emitted.

5  And it is not nearly as large a potential source of greenhouse gas as the methane hydrates that Japan (but also Canada itself) is attempting to exploit – see Hiroko Tabuchi, “An Energy Coup for Japan: ‘Flammable Ice’,” New York Times, March 12, 2013.  Swart & Weaver leave aside methane hydrates for which extraction is much less well developed.  Methane hydrates are thought to contain “at least twice the amount of carbon in all of the earth’s other fossil fuels”.

6  To simplify, and to be extremely conservative in my critique, I am ignoring further temperature rises already built into the system but not yet detectable.  Certainly business-as-usual entirely without the oil from the tar sands would carry us far past 2° C.

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