On Stabilization Wedges Theory – Introduction

One of the most interesting theories on climate change mitigation I came across was written by Robert Socolow and Stephen Pacala, professors at Princeton. This theory gives 15 ways to decrease our carbon dioxide emissions.

I first get to read about this article during summer 2006 and finally found the original paper last winter. This theory is so interesting that I first wanted to blog on that, but finally focused more on news articles and the likes. Now let us review Socolow and Pacala’s idea.

This work, first published in the United States in the magazine Science (issue of April 13, 2004) is interesting as it gives 15 different ideas to decrease our emissions and stabilize the amount of carbon dioxide into Earth atmosphere, hence the name.

Current emissions of carbon dioxide are at 7 GtC on a global scale. The trends indicate in a Business As Usual scenario (if nothing was done) a doubling of these emissions. According to the authors, taking seven of the fifteen possibilities would prove sufficient to do the job as all wedges account for the same emission’s reduction, ie. one billion ton of carbon per year (or GtC/year).

Thus, the seven wedges that would be chosen would stabilize the pollutions to 7 GtC per annum. Each stabilization wedge accounts for one billion ton of carbon per year. The most interesting founding is that any wedge, any effort among the fifteen account for the same decrease of carbon dioxide emissions. This is indeed a very powerful concept.

To quote the authors, the prospect is very optimistic as :

Humanity already possesses the fundamental scientific, technical, and industrial know-how to solve the carbon and climate problem for the next half-century. A portfolio of technologies now exists to meet the world’s energy needs over the next 50 years and limit atmospheric CO2 to a trajectory that avoids a doubling of the preindustrial concentration.

Every element in this portfolio has passed beyond the laboratory bench and demonstration project; many are already implemented somewhere at full industrial scale. Although no element is a credible candidate for doing the entire job (or even half the job) by itself, the portfolio as a whole is large enough that not every element has to be used.

(…)

Humanity can solve the carbon and climate problem in the first half of this century simply by scaling up what we already know how to do.

The wedges can be classified in five different categories :

1. Energy conservation with three wedges;
2. Electricity production with two wedges;
3. Carbon capture and storage with three wedges;
4. Alternative energy sources with five wedges;
5. Agriculture and forests exploitation with two wedges.

I will give the details of each wedge as well as some comments on this very interesting theory in the week, so stay tuned !

Sources :

The original article can be found via Google in several places including there.