Strategies toward ambitious climate targets usually rely on the concept of "decoupling"; that is, they aim at promoting economic growth while reducing the use of natural resources and GHG emissions. GDP growth coinciding with absolute reductions in emissions or resource use is denoted as "absolute decoupling", as opposed to "relative decoupling", where resource use or emissions increase less so than does GDP. Based on the bibliometric mapping in part I (Wiedenhofer et al., this issue), we synthesize the evidence emerging from the selected 835 peer-reviewed articles. We evaluate empirical studies of decoupling related to final/useful energy, exergy, use of material resources, as well as CO2 and total GHG emissions. We find that relative decoupling is frequent for material use as well as GHG and CO2 emissions but not for useful exergy, a quality-based measure of energy use. Primary energy can be decoupled from GDP largely to the extent to which the conversion of primary energy to useful exergy is improved. Examples of absolute long-term decoupling are rare, but recently some industrialized countries have decoupled GDP from both production- and, weaklier, consumption-based CO2 emissions. We analyze policies or strategies in the decoupling literature by classifying them into three groups: (1) Green growth, if sufficient reductions of resource use or emissions were deemed possible without altering the growth trajectory. (2) Degrowth, if reductions of resource use or emissions were given priority over GDP growth. (3) Others, e.g. if the role of energy for GDP growth was analyzed without reference to climate change mitigation. We conclude that large rapid absolute reductions of resource use and GHG emissions cannot be achieved through observed decoupling rates, hence decoupling needs to be complemented by sufficiency-oriented strategies and strict enforcement of absolute reduction targets. More research is needed on interdependencies between wellbeing, resources and emissions.

中文翻译：

---

对 GDP、资源使用和温室气体排放脱钩的证据的系统回顾，第二部分：综合见解

实现雄心勃勃的气候目标的战略通常依赖于“脱钩”的概念；也就是说，它们旨在促进经济增长，同时减少自然资源的使用和温室气体排放。GDP 增长与排放或资源使用的绝对减少一致被称为“绝对脱钩”，而不是“相对脱钩”，其中资源使用或排放的增长少于 GDP。基于第一部分（Wiedenhofer 等人，本期）中的文献计量映射，我们综合了从选定的 835 篇同行评审文章中出现的证据。我们评估与最终/有用能源、火用、物质资源使用以及二氧化碳和温室气体排放总量相关的脱钩实证研究。我们发现相对解耦对于材料使用以及温室气体和二氧化碳排放来说很常见，但对于有用的火用（一种基于质量的能源使用衡量标准）则不然。一次能源可以在很大程度上与 GDP 脱钩，以提高一次能源向有用火用的转化率。绝对长期脱钩的例子很少见，但最近一些工业化国家已将 GDP 与基于生产和较弱的基于消费的二氧化碳排放脱钩。我们通过将脱钩文献中的政策或战略分为三类来分析它们：（1）绿色增长，如果认为可以在不改变增长轨迹的情况下充分减少资源使用或排放。(2) 减增长，如果资源使用或排放的减少优先于 GDP 增长。(3) 其他，例如 如果在不参考减缓气候变化的情况下分析能源对 GDP 增长的作用。我们得出的结论是，资源使用和温室气体排放量的大幅快速绝对减少无法通过观察到的脱钩率实现，因此脱钩需要以充足为导向的战略和绝对减排目标的严格执行来补充。需要对福祉、资源和排放之间的相互依存关系进行更多研究。