The benefit of climate change policies: analytical and framework issues (executive summary)

This book considers how the benefits of climate change policy can be meaningfully conveyed to policy makers. This publication not only informs adaptation policy but also mitigation policy by helping to assess the trade-offs associated with different global mitigation pathways.The study argues that simple cost-benefit analyses where a single (monetary) measure compared with aggregate costs, may not be adequate on their own to inform policy decisions, especially given the incommensurable nature of benefits.It promotes the use of benefit-cost methods alongside risk-based methods, such as probabilistic approaches, to consider climate change and related impacts across a range of possible futures. A dual approach is required to develop a coherent set of indicators that present a balance of the physical and economic metrics of change. Benefits should be presented in at least two different forms: monetised estimates and physical impact estimates.Some general patterns emerge when looking across the literature on global climate change impacts and the benefits of mitigation policysome sectors, such as agriculture, may experience net positive impacts globally of a small amount of climate changeno research for any sector suggests positive impacts from climate change as temperatures increase beyond certain levelsa consistent pattern of marginal adverse impacts emerges across all sectors for which data were available beyond a 3-4 °C increase in global mean temperature – translating into possible large and positive net benefits to mitigation policies that can limit climate change to this level or possibly below itaccounting for the risks of irreversible, abrupt change is likely to increase the economically “optimal” level of mitigation, calling for more investment in abatement in the near-term.The full volume can be obtained by contacting: sales@oecd.org