The consensus view amongst economists is that carbon prices, in order to be effcient, must be the same across the globe. But when there are inefficiencies in the allocation of capital so that consumers in different countries face different discount rates, we show that efficient carbon prices...

Weitzman's Dismal Theorem has that the expected net present value of a stock problem with a stochastic growth rate with unknown variance is unbounded. Cost-benefit analysis can therefore not be applied to greenhouse gas emission control. We use the Generalized Central Limit Theorem to show that...

The economics of climate change involves a vast array of uncertainties, complicating both the analysis and development of climate policy. This study presents the results of the first comprehensive study of uncertainty in climate change using multiple integrated assessment models. The study looks...

We study adaptation to climate change in a federalist setting. To protect themselves against an increase in flood risk, regional governments choose among adaptation measures that vary with respect to their costs, the level of protection they offer, and the presence and nature of spillovers to...

Why do for-profit firms take voluntary steps to improve the environment? Brand appeal to green consumers or investors, the ability to influence or avoid regulation, or the experience gained for future regulation, have all been suggested as possible reasons. The empirical evidence is decidedly...

Climate change may intensify tropical cyclone activities and amplify their negative economic effects. We simulate the direct economic impact of tropical cyclones enhanced by climate change with the integrated assessment model FUND 3.4. The results show that in the base case, the direct economic...

We use FUND 3.5 to estimate the social cost of carbon dioxide, methane, nitrous oxide, and sulphur hexafluoride emissions. We show the results of a range of sensitivity analyses, focusing on the impact of carbon dioxide fertilization. Ignored in previous studies of the social cost of greenhouse...

It is well-known that the discount rate is crucially important for estimating the social cost of carbon, a standard indicator for the seriousness of climate change and desirable level of climate policy. The Ramsey equation for the discount rate has three components: the pure rate of time...

We apply four alternative decision criteria, two old ones and two new, to the question of the appropriate level of greenhouse gas emission reduction. In all cases, we consider a uniform carbon tax that is applied to all emissions from all sectors and all countries; and that increases over time...

A necessary condition of an efficient global climate change mitigation policy is to equate marginal abatement costs across world regions to ensure use of the cheapest abatement options available. The welfare economic justification for such an approach rests on lump sum transfers between regions...