Climate policy targets revisited

Tol on VoxEU: The IPCC’s Fifth Assessment Report estimates lower costs of climate change and higher costs of abatement than the Stern Review. However, current UN negotiations focus on stabilising atmospheric concentrations of greenhouse gases at even lower levels than recommended by Stern. This column argues that, given realistic estimates of the rate at which people discount the future, the UN’s target is probably too stringent. Moreover, since real-world climate policy is far from the ideal of a uniform carbon price, the costs of emission reduction are likely to be much higher than the IPCC’s estimates.