The Earth System Interventions Law and Policy Project (or ESI Project) at the UCLA Emmett Institute on Climate Change and the Environment is a pioneering initiative for legal and policy issues presented by interventions in the Earth System in response to escalating climate risk. Potential near-term interventions, including sunlight reflection (also known as solar radiation modification or SRM), glacier stabilization, and large-scale greenhouse gas removal, raise myriad issues from their societal impacts, risks, and benefits; their interactions with emissions-cutting measures and other climate responses; and related legal and policy challenges and potential responses.

Under the leadership of Edward A. Parson, Distinguished Dan and Rae Emmett Professor of Environmental Law and Faculty Director of the Emmett Institute, the ESI Project conducts interdisciplinary research, engages with and advises decision-makers, and educates broad audiences of students, professionals, and the public. It is supported by the LAD Climate Fund, The Navigation Fund, and the Ginkgo Fund, and received past support from Coefficient Giving (Open Philanthropy).

Our Work 

Since 2017, the ESI Project has advanced knowledge and legal and policy practice on Earth system interventions, taking account of both their potential contributions to effective climate response and their diverse risks.

Since the beginning of 2026, the project has co-convened three science-policy dialogues in Latin America with The Degrees Initiative, engaging more than 90 policymakers, over half of them sitting legislators, from 19 countries in intensive briefings and discussions on sunlight reflection. These dialogues have been hosted by the National Senates of Chile and Mexico as well as the Parliament of Latin America and the Caribbean (PARLATINO). PARLATINO adopted a declaration on SRM following the briefing.

• The project is leading the organization of an international summer institute on Earth system interventions governance in 2027 to train and educate early-career researchers and academics, based on its organizing role in prior summer schools.
• The project has produced more than 80 research publications since 2017, ranging from law review articles to books to a guest editorial in Science.
• The project's work reaches well beyond academia: its research has been cited in United Nations and governmental reports, and its experts are a regular source of commentary for outlets including The Economist and The Washington Post.
• The project was a close partner to the Climate Overshoot Commission, an independent international advisory body of 16 distinguished individuals from 14 countries, most of Ministerial or Head-of-Government rank. The project informed the design of the Commission and advised its work, including through student work in an international climate law clinic.

Background

Earth system interventions like sunlight reflection, glacier stabilization, and large-scale greenhouse gas removal are proposed intentional, large-scale modifications to the environment, which aim to counteract some of the harms from climate change. They promise, in dissimilar ways, the possibility of reducing climate-change risks more than is possible by emissions cuts and adaptation alone. They also present significant new risks and uncertainties.

Though emissions reductions should remain an urgent priority, Earth system interventions are entering public and policy debate. According to the United Nations, large-scale greenhouse gas removal will be necessary to achieve the Paris Agreement’s climate targets, but significant legal and policy development would be needed before that became a reality. Sunlight reflection, on the other hand, presents especially acute legal and policy challenges, but might be able to play a role in reducing some climate risks. Major concerns raised about sunlight reflection include potential unilateral use by one country, excessive or over-confident reliance that may weaken needed emissions-cutting efforts, and exacerbation of international inequity or conflict.