In this study about climate-change policy, the researchers explore different approaches to tackling the challenges of climate change. They discuss the concept of the social cost of carbon and how it impacts climate policies. The study delves into methods like tradable permits and carbon taxes as ways to address climate change. It also looks into the effectiveness of interventions like promoting renewable energy and improving energy efficiency. The researchers examine the Kyoto Protocol and discuss potential alternatives and future steps after Kyoto. They stress the importance of designing policies that can effectively reduce carbon emissions. Overall, the study aims to provide insights on how to best address the complex issue of climate change through various policy strategies and institutional designs.