Solar Geoengineering Non-Use Agreement

There are growing calls in recent years for research on “solar geoengineering“, a set of entirely speculative technologies to reduce incoming sunlight on earth in order to limit global warming. Our initiative stands against such emerging initiatives to explore planetary techno-fixes as a climate policy option. Solar geoengineering deployment at planetary scale cannot be fairly and effectively governed in the current system of international institutions. It also poses unacceptable risk if ever implemented as part of future climate policy. A strong political message from governments, the United Nations and civil society is urgently needed.

About

What is Solar Geoengineering?

Solar geoengineering (also known as solar radiation management or modification, SRM), refers to a set of speculative technologies to lower global temperatures by artificially intervening in the climate systems of our planet.

Read here our Open Letter calling for an International Non-Use Agreement on Solar Geoengineering

The Open Letter is based on an extended peer-reviewed perspective article published in WIREs Climate Change on 17 January 2022.

Non-Use Agreement

A call for 5 core commitments and measures

1No public funding

The commitment to prohibit national funding agencies from supporting the development of technologies for solar geoengineering, domestically and through international institutions.

2No outdoor experiments

The commitment to ban outdoor experiments of solar geoengineering technologies.

3No patents

The commitment to not grant patent rights for technologies for solar geoengineering, including supporting technologies such as for the retrofitting of airplanes for aerosol injections.

4No deployment

The commitment to not deploy technologies for solar geoengineering if developed by third parties.

5No support in international institutions

Resources

African Ministers Call for a Non-Use Agreement on Solar Geoengineering

During its July 2025 meeting, the African Ministerial Conference on the Environment (AMCEN) reaffirmed its unequivocal rejection of solar radiation modification technologies as having any role to play in addressing climate change. An overview of the relevant paragraphs related to these decisions can be found here.

Solar Geoengineering for Profit

In this blog post, a group of scholars supporting the call for an international non-use agreement on solar geoengineering responds to recent for-profit ventures in the field. The authors argue that these ventures are not rogue exceptions and caution that any future development of solar geoengineering—regardless of the intentions of scientists—risks appropriation by corporate and political actors.

Growing Scientific and Political Support for a Non-Use Agreement

Prof. Aarti Gupta, co-initiator of the initiative, discusses growing calls from governments in the Global South and academics for an international non-use agreement on solar geoengineering.

615+

Academics

have signed the Open Letter

Countries

represented by these academics

2000+

Organizations

have endorsed the Open Letter

5000+

Citizens

have signed the Petition

endorsed by

Quotes

Solar geoengineering is not necessary. Neither is it desirable, ethical, or politically governable. The normalization of solar geoengineering as a research topic and a speculative policy option must be stopped.

Solar geoengineering risks becoming a distraction from decisive climate action. We already count on speculative technologies because we don’t believe in changing our political and economic systems. Solar geoengineering is yet another example. It says it insures against the failure of climate politics. But if it becomes part of climate policy, that failure only becomes more likely

A speculative and highly risky techno-promise like solar geoengineering is a politically and ecologically dangerous distraction from what we actually need to do to address climate change: reduce entrenched inequalities and align our politics to help realize a just transition globally

In the vital efforts to build pathways to sustainable, socially-just futures amidst climate and environmental change, solar radiation management and other forms of geo-engineering have no place - indeed they are incompatible with the inclusive, democratic and plural processes that the world desperately needs.

The implications of SRM for all states are so pervasive that prior informed consent from all states and non-state stakeholders should precede SRM deployment, anything less runs counter to justice and equity.