The standard account of the climate change problem seems to be that developed countries got to where they are by recklessly exploiting resources, including the ability of the atmosphere to absorb greenhouse gases. These developed countries, therefore, need to take responsibility for solving the problem, the account goes. As Peter Singer puts it, "in terms a child could understand, as far as the atmosphere is concerned, the developed nations broke it. "
Is this account right? Answering that question breaks down into two parts: First, does the data support the conclusion that rich countries created the climate change problem? Second, even if the data does support that claim, does that mean that developed countries should bear more of the burden going forward?
Professor David Weisbach attempts to answer both parts in his paper "Responsibility for Climate Change, By the Numbers," presented at this week's Works in Progress (WiP) talk. The paper draws to some extent on recent work by Professors Cass Sunstein and Eric Posner in this area, and is connected to a forthcoming book project by all three professors.
Essentially, Weisbach argues that the conventional story is wrong on both counts - the data don't support a conclusion that rich states have contributed to the climate change problem significantly more than poor ones. Even if they did (Weisbach argues), an ethical theory that supported allocating more of the costs to developed countries today would be highly problematic, departing significantly with understandings of responsibility embodied in tort law.
In his paper, Weisbach takes data from environmental NGO World Resources Institute on contributions to climate change, and analyzes it in a variety of ways. The analysis shows that whether one considers total emissions, emissions per capita, emissions flows of the six most significant GHGs, atmospheric stocks of those gases, or other measures, including those that incorporate land use (de- and reforestation), the prediction that rankings of responsibility will come out showing rich countries with a significantly disproportionate share simply does not hold. Poor countries, on any of these measures, make a sizable contribution to the problem. For example, If one defines contribution to climate change as emission of the 6 most important GHGs plus land-use effects and ranks all countries, the top 20 emitters contribute 67% of the net impact on climate. But dividing those top 20 contributors into rich and poor groups (per capita GDP more or less than $20,000) gives surprising results - 40% of the total impact can be attributed to poor countries, and 27% to richer countries.
This holds true if one looks at historical, rather than current data, though different countries rank highly. It even holds true if one looks at per capita emissions - in that analysis, many poor countries such as Belize, Guyana, and Malaysia fare quite poorly. The United States ranks only 14th in this list (though its total emissions dwarf those of all countries ranked more highly).
Some might be suspicious of these results, concerned that they are manipulations of the data in a US-apologist fashion. Some commenters at the talk questioned, for example, whether definition of Russia and Eastern European countries as rich or poor might drive much of the counterintuitive conclusions. Weisbach's analysis seems quite robust, however. There is clearly more to be done here, and I would encourage those who doubt the results to examine the World Resources Institute data and draw their own conclusions, but none of the commenters were able to make a convincing critique of Weisbach's analysis.
As for me, I am somewhat concerned that while Weisbach's analysis of the data may be correct, it may not matter in actual climate negotiations. It seems likely that the really significant parties in that negotiation are going to be the US and China, and possibly also the EU and India. Brazil, Russia, and a few other medium-sized countries might get involved, but I tend to think that if the Big Two or certainly the Big Four emitters can hammer something out, the rest will follow. China and even more so India might be able to make the "developed countries are responsible" argument effectively within this small group, even if they could not do so globally. If this is the case, then that argument would have much greater relevance for the obligations in an eventual treaty than Weisbach's analysis of the data indicates. I'd be interested to see how the various analyses Weisbach includes in his paper look when they are limited to a much narrower class of big emitters, though admittedly that limited set of data would not address the broader responsibility claims that the paper in its current form is aimed at.
Some commenters did make deeper criticisms, for example arguing that it might be unreasonable or inequitable to charge colonized countries with responsibility for emissions made before independence, or that changing borders and governments might similarly make assigning blame problematic. Weisbach argued, convincingly I think, that these are complex ethical questions really beyond the scope of his analysis, and that the data itself is limited in some important respects. Nevertheless, advocates of the standard "developed countries broke it" position at least purport to be arguing from the same data. Weisbach's analysis therefore forces them to be more up front about their analysis of the data, and the ethical theories underpinning their allocation of responsibility.
The paper and talk also delved into the question of whether it is reasonable to argue that developed countries should bear a higher proportion of future climate-related costs, even if the responsibility story is true. Weisbach argued that, as compared to traditional ethical theories as embodied in tort law, this argument for an obligation to pay lacked the traditional elements of fault and a close connection between the actor and the injured party. The presence of poorer countries on the lists of responsible parties also raises distributional concerns, Weisbach noted.
To put this more clearly, is it reasonable to hold someone living in, say, Norway who heated their home in 1960 (emitting GHGs as a result) responsible for climate change such that citizens of Norway today should be asked to pay that "share" of warming? In what sense is that person blameworthy? Should they have moved somewhere warmer? How can we compare their blameworthiness to someone driving to work in 1990? How far is too far to drive, or how big of a car is too big? One commenter urged Weisbach to take this argument even further, suggesting that we should consider not only the negative climate externalities of energy expenditure, but also the positive externalities associated with most economic activity. Is the researcher in a lab (whose work may lead to more efficient technology in the future) blameworthy? What about the movie studio - should we discount the consumer surplus that moviegoers get from the negative climate effects of the energy used to make the movie? Should producers or consumers of goods and services be held responsible for the climate impact of their production? The more one thinks about the problem, the more problematic the (admittedly superficially compelling) standard responsibility account becomes. Weisbach correctly observes that these questions implicate deep issues not only in tort law, but in ethics generally - causation, fault, responsibility, and attribution all go back to Aristotle, or further.
So What Do We Do?
If the data and the ethics of the climate change problem make a solution much more complex than the standard account of responsibility would have us believe, what are thoughtful, concerned people supposed to do about the problem?
Part of the answer to this has to be, as Weisbach noted during the talk, that answering the data and ethical questions might not matter so much. The solution - presumably a global climate treaty - will be shaped by politics and negotiation. Interpretation of the data, and moral arguments based on a combination of that data with an ethical theory, are ultimately rhetorical tools in negotiating the treaty. It doesn't matter so much which we adopt, or even if different parties adopt different theories (or none at all) - the result will likely be much the same, and we (or at least everyone but academics), can move on and tackle the problem under whatever framework is decided.
Nevertheless, these are undoubtedly hard questions, and if one wants to understand the problem (rather than simply taking a negotiating position), they must be confronted. Climate change is often characterized as the problem of our time. This is generally meant in the sense that the problem is big, and the risks large. Weisbach's paper illustrates this same characterization in another way - it is a defining problem because it reaches so deeply into fundamental issues across fields. The scientists have to get it right and provide accurate basic data and predictions. Economists and statisticians have to correctly analyze and interpret that data. At some level in this interpretation, however, decisions cease to be about what is correct and incorrect and start to involve what is right and wrong in an ethical sense - and this requires a discussion that reaches into the oldest problems in society. Further, these issues will not play out in labs and classrooms alone, but ultimately on an international stage, where power and influence matter. Forming and enforcing any agreement finally depends on law.
To put it simply, climate change is a Hard Problem - no surprises there. It requires work by specialists and by generalists who understand all these fields, but even then the challenges are great. While the professors at the WiP had many intelligent comments, I have never seen a room full of law professors who all seemed to acknowledge that, for once, they don't have the answer - or at least not the whole answer. Weisbach's paper isn't (and does not claim to approach) that answer either, but it is, I think, a small example of the kind of thoughtful, polymathic work that will be required to move the world towards a solution to climate change. I very much look forward to the upcoming book, and hope that it contains more of the same.