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If there were any doubt that the proposed Keystone XL pipeline—which would bring more than 700,000 barrels a day of Canadian oils sands through the Midwest to refineries in the U.S.—has become the biggest environmental issue in America, this week should have quieted them. On Monday at 12 PM ET a coalition of major environmental groups led by the writer-turned-activist Bill McKibben launched a 24-hour effort to gather half a million signatures for an online petition urging the Senate to block a Republican-led effort to force approval of the pipeline, which had been rejected by President Obama in January. They managed to hit their target within hours, and ultimately delivered more than 800,000 signatures from people opposed to the pipeline, as McKibben described:

Over 800,000 Americans made it clear that Keystone XL is the environmental litmus test for Senators and every other politician in the country. It’s the one issue where people have come out in large numbers to put their bodies on the line, and online too: the largest civil disobedience action on any issue in 30 years, and now the most concentrated burst of environmental advocacy perhaps since the battles over flooding the Grand Canyon back in the glory days.

The Keystone Senate amendment is in limbo, and it’s far from clear that Congress could legally force approval for a construction project that had required the White House’s signoff—even assuming Obama wouldn’t simply veto the measure. But for Republicans and their allies in the oil industry it might not even matter. They see Keystone as a potent campaign issue, proof that Obama would choose his environmental allies over a construction project that could bring jobs and oil from a friendly nation, even as the U.S. economy struggles to recover and the Iranian crisis highlights just how unstable Mideast oil is. At the same time, though, an environmental movement that had stalled after the failure of cap-and-trade and the conservative wave in 2010 have found in Keystone a battle worth fighting—and even more importantly, one that fires up the grassroots.

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I have a magazine story about McKibben and his fight against the pipeline coming out soon, so I’ll hold my fire on the Keystone question for now. (Though I’ve written about in the past here, here and here—it’s been good for environment writers too.) Obviously the gap between greens and most conservatives on Keystone is a wide one, and I doubt there’s much persuasion going on between the two sides.(The American public, for the most part, seems relatively split on the issue—some polls show support for the pipeline and some show opposition, depending on how the questions are framed.) But I am interested in how the pipeline debate has become divisive among some climate/energy analysts and advocates who are often on the same side—and how it demonstrates the different ways both approach the big problems.

Let’s start with the New York Times. Earlier this month the Op-Ed columnist Joe Nocera—who most often writes about economics when he’s not pursuing an awesomely righteous crusade against the hypocrites who run the NCAA— wrote a column chastising President Obama for blocking the Keystone pipeline. He got in a back and forth with Joe Romm of ClimateProgress, and wrote another column responding to the criticism:

Here’s the question on the table today: Can a person support the Keystone XL oil pipeline and still believe that global warming poses a serious threat? To my mind, the answer is yes. The crude oil from the tar sands of Alberta, which the pipeline would transport to American refineries on the Gulf Coast, simply will not bring about global warming apocalypse. The seemingly inexorable rise in greenhouse gas emissions is the result of deeply ingrained human habits, which will not change if the pipeline is ultimately blocked. The benefits of the oil we stand to get from Canada, via Keystone, far outweigh the environmental risks.

Nocera quoted Michael Levi of the Council on Foreign Relations: “The argument you hear is that because it increases greenhouse gas emissions, we shouldn’t tolerate it. Well, so do the lights in my house. You have to be discriminating.”

This is a key point, and one Romm—who also does not back down from a fight—picked on:

That may be the lamest analogy in the history of energy and climate. Nocera is actually analogizing the GHG emissions increase from 900,000 barrels a day of dirty tar sands oil with flicking on the lights in your house! And remember, Nocera wants a lot more oil than that. How bad is this analogy? Many people choose to get their electricity from renewable sources — so for them turning on the lights don’t even increase GHGs. The point is people don’t have any choice about the dirty tar sands oil — but Obama does.

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Levi responded on his own blog, pointing out that—by the numbers at least—he was correct:

It isn’t enough to just say “there’s a ton of carbon there” in order to argue that we shouldn’t do something. You can do that with way to many things – including, yes, turning on your lights. As I told Nocera, we need to be discriminating: there are big pools of carbon that are worth burning, and there are big pools of carbon that aren’t. Well meaning people can disagree as to whether 900,000 barrels a day of tar sands oil falls in the former category or the latter one. The mere fact that the pool in question is big isn’t enough alone to place it off limits.

Levi has poked holes with the arguments of the anti-Keystone pipeline forces before (as well as those from the pro-pipeline side). He’s noted that former Vice President Al Gore was simply wrong to write that a Prius running gasoline from oil sands crude was worse for the climate than a Hummer running on gasoline from conventional crude, and he effectively shot down the argument that Keystone will do little for energy security because much of the oil will be refined and then exported. He echoed Andrew Leach at the University of Alberta’s point that while the climatologist James Hansen has said that burning all the crude in the oil sands would be “game over” for the climate, it would take more than 1,000 years to extract all that oil even at an accelerated rate—by which time, presumably, other factors will have decided the climate question. (Or, I don’t know, by which time an asteroid will have hit the planet or aliens will have invaded.)

Levi and some of the other writers—like Andrew Revkin of Dot Earth—who’ve been skeptical of some of the anti-Keystone arguments have come for criticism for, essentially, not getting behind the cause. McKibben and his allies are quite open about the fact that they see the Keystone battle as a political one, with the ultimate aim of preventing the exploitation of the oil sands altogether. Stopping the pipeline is a temporary win, but one that can hopefully build momentum for more victories, from stopping the alternate Northern Gateway pipeline that would take oil sands crude to Canada’s west coast and then to China to supporting the kind of broader climate action—a carbon tax, cap-and-trade—that would be needed to really deal with the problem. Specific numbers matter here less than keeping the political pressure on in the face of the well-armed opposition of fossil fuel interests.

To the analysts, though, numbers matter—including the numbers behind the sheer size Canada’s oil sands reserves, which may hold nearly 200 billion barrels of recoverable oil, and perhaps far more. As Nocera suggests in his column, the chance of Canada—which is becoming ever more reliant on its energy industry—simply leaving trillions of dollars worth of money in the ground is incredibly unlikely. By that calculation, last month’s rejection of the Keystone pipeline, which is still far from dead, is just a speed bump to the exploitation of that resource, barring some kind of top down policy that manages to significantly reduce world oil demand.

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In an incisive post yesterday George Hoberg of the University of British Columbia explained why analysts and advocates are butting heads over Keystone:

The analysts’ essential argument is two-fold. First, given the amount of GHG emissions enabled by the pipeline and the nature of North American and especially global oil markets, the marginal impact of the KeystoneXL pipeline on global GHGs will be insignificant. Second, there are much more cost-effective ways to reduce GHG emissions than blocking pipelines. I believe that both are these arguments are unquestionably correct. But I also believe that they completely miss the point about why environmentalists are so opposed to the KeystoneXL. The logics of analysis and advocacy are fundamentally different. The analyst is guided by aspirations for truth and well-reasoned argument, and guided largely by the value of maximizing the cost-effectiveness of solutions. They chaff against exaggerations and misuse of data by advocates on all sides, and search for the best reasoned argument for the most efficient path forward.

Climate advocates, by contrast, is trying to maximize political leverage, and as Hoberg writes, that may involve “exaggerated claims that aggravate the analyst.” But Hoberg—while he has sympathies for the analyst’s approach—says he ultimately believes a “leap of faith” is needed to convince policymakers and the public to act from moral rather than economic grounds. So great is the climate challenge—and so overwhelming is the opposition—that if we let ourselves be defined by the numbers, we will fail.

It’s as cogent an a dissection I’ve seen of why analysts and advocates—and I consider myself much more the former—might differ on Keystone. I’d only add that climate advocates have long prided themselves—and indeed, built their case—on the fact that they have science and numbers on their side. Think of Gore and his Climate Reality project, and the constant invocation of “the science” that demands action. So it shouldn’t be surprising that climate advocates might get less wiggle room on factual fidelity than their opponents—even though climate skeptics, as the leaked documents (or hacked, as the case may be) from the Heartland Institute indicate, have no qualms about gaming the system. As McKibben and his allies are learning—and learning well—it takes much more than science to win at politics.

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