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The complex international regime for climate change has evolved over the past three decades, from the Framework Convention on Climate Change and the Kyoto Protocol through the Paris Agreement and beyond. We assess this evolution from the 1990s to the 2020s, and its potential future evolution from the 2020s to the 2050s, across three main policy strategies: mitigation, adaptation, and reflection. In its first three decades, the regime has focused predominantly on the mitigation of net emissions and on engaging all major emitting countries in that effort. More recently, as progress on mitigation has been slow and as the impacts of climate change have risen around the world, the regime has begun to address adaptation. The next three decades may see the rise of a third strategy, reflection, if actors (collectively or unilaterally) perceive an urgent need to alleviate peak climate damages through fast-acting but controversial and risky climate interventions known as sunlight reflection methods or solar radiation modification (SRM). Several major international groups have recently issued reports on SRM, yet the international climate change regime has not yet constructed a governance regime for assessment or management of SRM. We recommend and outline comprehensive risk-risk tradeoff analyses of SRM to help avoid harmful countervailing risks. We suggest the development of an adaptive governance regime, starting early and embracing iterative and inclusive learning and updating over time. We urge that among the first key steps should be the development of a transparent international monitoring system for SRM. Such a monitoring system could provide early warning and help deter any unilateral SRM, assess the intended and unintended global and regional impacts of any research or eventual deployment of SRM, foster collective deliberation and reduce the risk of international conflict over SRM, help attribute adverse side effects of SRM to assist those adversely affected, and aid learning to improve the system adaptively over time. Thus, any reflection (of sunlight) should involve ongoing reflection (analysis and revision). Such an SRM monitoring regime is needed before SRM might be deployed, and can be developed at the same time that the focus of current efforts remains on mitigation and adaptation.
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This content will become publicly available on June 6, 2026
Models and scenarios for solar radiation modification need to include human perceptions of risk
Abstract Solar radiation modification (SRM) is a climate intervention method that would reflect a portion of incoming solar radiation to cool the Earth and could be used to ameliorate the impacts of climate change, but that provokes strong reactions from experts and the public alike. Research has explored both the biophysical and human behavioral aspects of SRM but has not integrated these processes in a single framework. Our expectations for SRM development and deployment will be inaccurate until we integrate the feedbacks between human behavioral and cognitive processes and the biophysical and climate system. We propose a framework for describing these feedbacks and how they may mediate transitions in the development and operationalization of SRM as a climate intervention. We consider components such as public trust in SRM, moral hazard concerns, climate risk perceptions, and societal disruptions, and illustrate how the driving processes could change across the pre-development, post-development, and post-deployment phases of SRM operationalization to affect outcomes around SRM deployment and climate change. Our framework illustrates the importance of feedbacks between climate change, risk perceptions, and the human response and the necessity to integrate such feedbacks in the development of future scenarios for SRM.
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- Award ID(s):
- 2436120
- PAR ID:
- 10638472
- Publisher / Repository:
- IOPScience
- Date Published:
- Journal Name:
- Environmental Research: Climate
- Volume:
- 4
- Issue:
- 2
- ISSN:
- 2752-5295
- Page Range / eLocation ID:
- 023003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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