Climate change involves uncertain probabilities of catastrophic risks, and very longterm consequences of current actions. Climate economics, therefore, is centrally concerned with the treatment of risk and time. Yet conventional assumptions about utility and optimal economic growth create a...

The social cost of carbon - or marginal damage caused by an additional ton of carbon dioxide emissions - has been estimated by a U.S. government working group at $21/tCO2 in 2010. That calculation, however, omits many of the biggest risks associated with climate change, and downplays the impact...