A Critique of Climate Economics Skepticism

Project completed September 2014.

Richard Tol's 2013 review article, "Targets for global climate policy," has been widely cited as a definitive statement on the economics of climate change, and was the sole source for portions of the recent IPCC reports. Synapse reviewed the article and found it to be unreliable in three major respects. First, it asserts that only 16 studies, a repetitive and dated subset of the research literature, represent the extent of knowledge about the economic impacts of climate change. Second, it identifies a large number of estimates of the "social cost of carbon," but then focuses almost exclusively on the minority of estimates that assume a high discount rate. Third, its estimate of the cost of large-scale emission reduction is based on an ad hoc extrapolation from model results for more modest reduction targets. As a result of these flaws, the article's recommendation of a very low carbon price and "optimal" CO2 levels above 600 ppm should not be relied on.