Here is perhaps my most succinct and citable explanation of why “Both national and global climate policy (PDF) must redirect its focus from setting a price on carbon to promoting the rapid deployment of clean technologies” (online here).

True, I didn’t think I would appear in Nature again. But Nature online asked me for my critique of the Boxer-Lieberman-Warner Bill bill, and they were open to a big-picture commentary based on the latest climate science. They even ran with a modified version of my proposed wedges solution (see below, longer version here). The central conclusion of the paper is the major theme of my work:

The latest science suggests that national and global climate policy is seriously misdirected. We must aim at achieving average annual carbon dioxide emissions of less than 5 GtC [5 billion metric tons of carbon] this century or risk the catastrophe of reaching atmospheric concentrations of 1,000 p.p.m. A carbon price set by a cap-and-trade system is a useful component of a longer-term climate strategy. Implementing such a system, however, is secondary to adopting a national and global strategy to stop building new traditional coal-fired plants while starting to deploy existing and near-term low-carbon technologies as fast as is humanly possible.

What are the “series of aggressive strategies for technology deployment” we need?

… tax credits, loan guarantees or other incentives for low-carbon technology, demonstration projects of technologies such as carbon capture and storage, a standard for electricity generation involving renewable or low-carbon options, a low-carbon fuel standard, tougher standards for fuel economy and appliances, and utility regulations that create a profit for investments in efficiency. These are all features of the climate plan of the Democratic presidential nominee, Barack Obama (PDF), but are not part of the announced climate strategy of Republican presidential nominee John McCain, whose plan starts by allowing unlimited offsets.

I am especially delighted that they created a figure for me of the wedges (click for larger version):


They even ran my full caption/caveat:

Figure 1 Strategy for stabilization. The top line represents business-as-usual global carbon emissions (in GtC) from fossil fuel combustion projected through 2070. Each of the 11 coloured wedges represents a different climate strategy that is deployed globally beginning in 2020 and avoids 1 GtC/year by 2070. Continued through 2100, this flat emissions path of 11 GtC/year would bring global carbon dioxide concentrations of 1,000 p.p.m. if accompanied by climate-carbon-cycle feedbacks anticipated by the IPCC. The `wedges’ approach is not analytically rigorous in that Socolow and Pacala do not know the business-as-usual baseline — they don’t specify, for instance, how many nuclear plants will be built in the absence of climate policies. Because the IPCC’s own economic models do not present a clear baseline, this should not be seen as a fatal flaw; nonetheless, the wedges above should be taken as qualitative rather than prescriptive. Strong efforts would also be required to decrease other greenhouse gases, but they are not the focus of this article. This figure is inspired by Socolow and Pacala’s stabilization wedges but does not represent the views of the original paper’s authors or of Princeton University’s Carbon Mitigation Initiative. Modified from the original with permission from Princeton University and AAAS.

I should hasten to add that I still think the optimum strategy is about 13 or 14 wedges implemented in about 35 to 40 years, as the International Energy Agency does (see “IEA report, Part 2“). But I went with 11 wedges here (implemented in 50 years or 25 years) for reasons that will be clear when you read the analysis — basically I’m trying to show the policy difference between “stabilizing” at 1000 ppm and stabilizing at 450 ppm, namely that the latter requires a massive and rapid deployment of existing and near-term technology.

Needless to say, I disagree with Roger Pielke, Jr.’s Nature piece (first quote) and agree with Pacala and Socolow (second quote):

Although it has recently been argued that “enormous advances in energy technology will be needed to stabilize atmospheric carbon dioxide concentrations at acceptable levels”, on the contrary it would seem that “humanity already possesses the fundamental scientific, technical, and industrial know-how to solve the carbon and climate problem for the next half-century.”

And again, needless to say, a focus on breakthrough technologies, though rhetorically compelling, is misdirected:

In fact, such is the urgent need to reverse emissions trends by deploying a multitude of low-carbon technologies that we must rely on technologies that either are already commercial or will very shortly be so. Fortunately, venture capitalists and public companies have begun to inject many billions of dollars into the development and short-term commercialization of most plausible low-carbon technologies. Governments should now focus their R&D spending on a longer-term effort aimed at a new generation of technologies for the emissions reduction effort after 2040, but the notion that we need a Manhattan Project or Apollo programme for technology development is mistaken. Instead, what is urgently needed is an effort of that scale focused on the deployment of technology.

Supposedly game-changing energy breakthroughs, even if they were an outcome we could reliably depend on — which they are not — don’t in fact change the “game,” which is a massive and rapid deployment of existing and near-term technology. For a longer discussion of this point, see “The breakthrough technology illusion.”

Finally, they let me include a much-shortened version of why stabilizing at 550 ppm is not really a superior strategy, even if it is possible, which it probably isn’t:

Some may believe that stabilizing atmospheric carbon dioxide concentrations below 450 p.p.m. is so difficult that we should seek to stabilize them at 550 p.p.m. or higher. But from a policy perspective, stabilizing at 550 p.p.m. is not much easier to achieve than leveling off at 450 p.p.m. — it still requires employing the vast majority of the wedges described here in under five decades, starting very soon. And yet the scientific evidence suggests that reaching 550 p.p.m. could have much graver consequences, for example destroying a large fraction of the permafrost, which houses a third of the carbon stored in soils globally. Much of this carbon would be released in the form of methane, a far more potent greenhouse gas than carbon dioxide, and could thus trigger more rapid climate change. Delay therefore risks crossing climate thresholds that would make efforts at emissions reduction far harder, if not almost impossible.

For a longer analysis of the tundra problem, see “Slip of the tundra.”

I hope this piece will stir up discussion and maybe some action, as I really, really don’t want to subject future generations to the horror of 1000 ppm (see”Is 450 ppm politically possible? Part 2.5“).

No one will ever forgive our generation if we do that. Nor should they!

This post was created for, a project of the Center for American Progress Action Fund.