摘要：The climate benefit and economic cost of an international mechanism for reducing
emissions from deforestation and degradation (REDD) will depend on the design of
reference levels for crediting emission reductions. We compare the impacts of six
proposed reference level designs on emission reduction levels and on cost per emission
reduction using a stylized partial equilibrium model (the open source impacts of
REDD incentives spreadsheet; OSIRIS). The model explicitly incorporates national
incentives to participate in an international REDD mechanism as well as international
leakage of deforestation emissions. Our results show that a REDD mechanism can
provide cost-efficient climate change mitigation benefits under a broad range of
reference level designs. We find that the most effective reference level designs balance
incentives to reduce historically high deforestation emissions with incentives to
maintain historically low deforestation emissions. Estimates of emission reductions
under REDD depend critically on the degree to which demand for tropical frontier
agriculture generates leakage. This underscores the potential importance to REDD of
complementary strategies to supply agricultural needs outside of the forest frontier.
