Counting Only the Hits? The Risk of Underestimating the Costs of Stringent Climate Policy

This paper warns against the risk of underestimating the costs -and the uncertainty about the costs- of achieving stringent stabilization targets. We argue that a straightforward review of integrated assessment models results produces biased estimates for the more ambitious climate objectives such as those compatible with the 2øC of the European Union and the G8. The magnitude and range of estimates are significantly reduced because only the most optimistic results are reported for such targets. We suggest a procedure that addresses this partiality. The results show highly variable costs for the most difficult scenarios.