Carbon Border Adjustments, Climate Clubs, and Subsidy Races When Climate Policies Vary
研究了不同国家气候政策（碳定价与清洁生产补贴）差异导致的两种政策溢出效应，分析了碳边境调整和气候俱乐部如何应对这些溢出，并探讨了补贴竞赛的风险与收益。
Jurisdictions adopt climate policies that vary in terms of both ambition and policy approach, with some pricing carbon and others subsidizing clean production. We distinguish two types of policy spillovers from these diverse approaches. First, when countries have different levels of climate ambition, free-riders benefit at the expense of more committed countries. Second, when countries pursue different approaches, carbon-intensive producers within cost-imposing jurisdictions are at a relative competitive disadvantage compared with producers in subsidizing jurisdictions. Carbon border adjustments and climate clubs respond to these spillovers, but when countries have divergent approaches, one policy alone cannot address both spillovers. We also consider the policy dynamics arising from carbon border adjustments and climate clubs; both have the potential to encourage upward harmonization of climate policy, but come with risks. Further, the pressures of international competition may result in subsidy races, with attendant risks and benefits.