About 45 years ago a few economists offered the novel idea of trading pollution rights as a way of meeting environmental goals. Such trading was touted as a more cost-effective alternative to traditional forms of regulation, such as specific technology requirements or performance standards. The...

Nearly all discussions about the appropriate consumption discount rate for climate-change policy evaluation assume that a single discount rate concept applies. We argue that two distinct concepts and associated rates apply. We distinguish a social-welfare-equivalent discount rate appropriate for...

This paper reveals significant unintended consequences from recent 14-state efforts to reduce greenhouse gas emissions through limits on greenhouse gases per mile from new cars. We show that while such efforts significantly reduce emissions from new cars sold in the adopting states, they cause...