Climate modelers have recognized the possibility of abrupt climate changes caused by a reorganization of the North Atlantic's current pattern (technically known as a thermohaline circulation collapse). This circulation system now warms north-western Europe and transports carbon dioxide to the...

This paper considers the question of under what circumstances a new environmental regulation should "phase in" gradually over time, rather than being immediately implemented at full force. The paper focuses particularly on climate policy, though its insights are more general. It shows that while...