Department of Biological Sciences, Boise State University, Boise, ID 83725;
Department of Agricultural, Environmental and Development Economics, The Ohio State University, Columbus, OH 43210.
Proc Natl Acad Sci U S A. 2019 Dec 3;116(49):24492-24499. doi: 10.1073/pnas.1904027116. Epub 2019 Nov 18.
Reducing emissions from deforestation and forest degradation (REDD+) is a climate change mitigation policy in which rich countries provide payments to developing countries for protecting their forests. In 2009, the countries of Norway and Guyana entered into one of the first bilateral REDD+ programs, with Norway offering to pay US$250 million to Guyana if annual deforestation rates remained below 0.056% from 2010 to 2015. To quantify the impact of this national REDD+ program, we construct a counterfactual times-series trajectory of annual tree cover loss using synthetic matching. This analytical approach allows us to quantify tree cover loss that would have occurred in the absence of the Norway-Guyana REDD+ program. We found that the Norway-Guyana REDD+ program reduced tree cover loss by 35% during the implementation period (2010 to 2015), equivalent to 12.8 million tons of avoided CO emissions. Our analysis indicates that national REDD+ payments attenuated the effect of increases in gold prices, an internationally traded commodity that is the primary deforestation driver in Guyana. Overall, we found strong evidence that the program met the additionality criteria of REDD+. However, we found that tree cover loss increased after the payments ended, and therefore, our results suggest that without continued payments, forest protection is not guaranteed. On the issue of leakage, which is complex and difficult to quantify, a multinational REDD+ program for a region could address leakage that results from differences in forest policies between neighboring countries.
减少森林砍伐和退化所致排放(REDD+)是一种气候变化缓解政策,富裕国家为发展中国家保护森林提供付款。2009 年,挪威和圭亚那两国签订了首批双边 REDD+计划之一,根据协议,如果 2010 年至 2015 年期间,圭亚那的森林砍伐率保持在每年 0.056%以下,挪威将提供 2.5 亿美元。为了量化该国家 REDD+计划的影响,我们采用合成匹配构建了一个假想时间序列的年度森林覆盖损失轨迹。这种分析方法使我们能够量化在没有挪威-圭亚那 REDD+计划的情况下可能发生的森林覆盖损失。我们发现,在执行期间(2010 年至 2015 年),挪威-圭亚那 REDD+计划使森林覆盖损失减少了 35%,相当于避免了 1280 万吨 CO2 排放。我们的分析表明,国家 REDD+付款减轻了国际交易商品黄金价格上涨的影响,黄金是圭亚那的主要森林砍伐驱动因素。总体而言,我们发现有强有力的证据表明该计划符合 REDD+的额外性标准。然而,我们发现,在付款结束后,森林覆盖损失增加了,因此,我们的结果表明,如果没有持续付款,森林保护就无法得到保证。关于复杂且难以量化的泄漏问题,一个地区的跨国 REDD+计划可以解决由于邻国森林政策差异而导致的泄漏问题。