Climate change: how to decide who pays

Cass Sunstein points out that:

[i]t is increasingly clear that the world would be better off with an international agreement to control greenhouse gas emissions. What remains poorly understood is that the likely costs and benefits of emissions controls are highly variable across nations.

The US and China, large emitters of greenhouse gases, are not likely to be the leading victims of climate change. Indeed, and with all the usual caveats, Russia is expected to gain. The biggest projected losers from climate change are India and Africa. The mismatch between the large emitters and and those most at risk contributes to the current policy stalemate. Adding to the complexity, a country like China could point to cumulative emissions as a basis on which to allocate blame and so responsibility for cutting emissions: Sunstein gives a table showing that the US emitted 29% of the total (anthropogenic) carbon dioxide from 1850-2002; China 7.6%. Or perhaps per capita emissions should be the criterion? On that basis, the US emitting 19.7 tonnes of CO2 (in 2002) is far more culpable than China (3.7 tonnes).

Sunstein concludes that:

Because of its wealth, its high per capita emissions rate, and its past contributions, the moral obligations of the United States are especially insistent. What remains clear is that the United States cannot do much about the problem without the participation of developing countries, above all China. For this reason, it is appropriate for the United States to take active steps, perhaps including unilateral action, in order to increase the likelihood that such countries will be willing to participate in the future.

Agreed, appropriate yes, but also unlikely. Sunstein's discussion is compelling, but I'd still prefer to see an outcome-based approach, such as Climate Stability Bonds that would rely on upfront cash incentives, instead of the vagaries of moral suasion. The two are need not be in conflict of course. but I'd rather back a regime that rewards self interest. At the highly aggregated level of countries, that seems to me more likely to work, and that, after all, is what really matters.