Decarbonization scenario ensembles are increasingly used for policy design, company strategy, and stakeholder engagement. However, the limitations of these scenarios may not be adequately understood. We summarize the uses and challenges with applying decarbonization scenarios to inform policy and planning decisions by using a novel database of U.S. net-zero CO2 emissions scenarios. Models agree that power sector emissions reductions, wind and solar deployment, end-use electrification, energy efficiency, and carbon removal help to reach economy-wide net-zero emissions; however, there is considerable variation in these changes, which may not be reflected in current third-party guidance or international pledges. We show how there is more regional variation in decarbonization pathways than national modeling indicates. The analysis also compares U.S. national scenarios with corresponding U.S. results from global models and finds that models can vary widely in their sectoral emissions reductions, use of carbon removal, and renewables deployment.

中文翻译：

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国家脱碳情景的使用和限制为净零转型提供信息


脱碳情景集合越来越多地用于政策设计、公司战略和利益相关者参与。然而，这些情景的局限性可能没有得到充分理解。我们通过使用美国净零 CO2 排放情景的新数据库，总结了应用脱碳情景为政策和规划决策提供信息的用途和挑战。模型一致认为，电力部门减排、风能和太阳能部署、最终用途电气化、能源效率和碳去除有助于实现整个经济的净零排放;但是，这些变化存在很大差异，这些变化可能不会反映在当前的第三方指南或国际承诺中。我们展示了脱碳路径的区域差异如何比国家模型显示的要多。该分析还将美国国家情景与来自全球模型的相应结果进行了比较，发现模型在部门减排、碳去除使用和可再生能源部署方面可能有很大差异。