Wednesday, 14 May 2025

Important Updates

• If you’ve not already confirmed your attendance, tonight’s conference dinner is now full. Shuttles leave at 16:00. 

• When time permits today, please complete the Degrees Global Forum SRM Survey.

Seen and Heard

Highlights from today's activities. Read on below for takeaways from each session.

Join the Conversation

Want to stay in the loop during the day's sessions – or share something we should be sure not to miss? Connect with us on LinkedIn, Bluesky, and X using the conference hashtag #DGF2025.

Supporting Materials from SRM360

Quiz Time: Through 2024, the Global North received approximately how much more SRM funding than the Global South?

Use our new Funding Tracker to explore who's funding – and who's receiving funding for – solar geoengineering research. Be sure to join us during this morning's New Initiatives session at 10:10 to learn more.

In Case You Missed It: Day 2 Recap

Opening Plenary: Live podcast discussion: SRM and Africa – perspectives from the continent

In a live podcast session, African experts shared their hopes and concerns about SRM and Africa’s future. “I see a future brimming with opportunities but fraught with challenges”, said Ernest Ofori. “We cannot separate economic from climate needs”, said Portia Adade Williams. 

Discussing SRM’s climate consequences, Babatunde Abiodun said: “The biggest concern is the impact on water availability." Nana Browne Klutse closed the session by reflecting on decisions around deployment: “No country is ready to do that until we convince ourselves of the risks. Is it going to trade off water? Air? We need to clearly understand what will happen if we have to do it.”

New Initiatives

Four relative newcomers to the SRM community introduced themselves following the opening plenary:

Green Africa Youth Organization (GAYO) works directly with local communities to reduce the vulnerability of groups that are at risk to climate impacts, such as children, youth, and women.

SRM Youth Watch is a youth and global south-led initiative concerned about the lack of sufficient international governance around SRM, but also the lack of awareness and engagement in governance discussions amongst young people.

World Climate Research Programme Lighthouse Activity coordinates research around some of the most pressing scientific questions in relation to the compounded nature of the climate system, to find answers together with all nations, looking at it from a multitude of disciplines.

African Climate Research Hub emphasises that responsible SRM research in Africa is  essential for informing regional climate policy. The group released a statement yesterday in response to Hands Off Mother Earth (HOME) Alliance's opposition to the Degrees Global Forum. 

Evening Plenary: SRM in a fractured world

Moderated by Dan Schrag, the afternoon plenary featured international climate policy experts who discussed how SRM fits in the context of our fractured world.

Baroness Worthington said: “It’s so late in the day… we need to try as many opportunities as possible to buy us some time. I see [SRM] as a time machine.”

Todd Stern also sees SRM as a path worth exploring: “We should go full speed ahead on [SRM] research”, while underscoring the “fundamental importance of decarbonising”.

“It has to start from somewhere”, said Nana Ama Browne Klutse. “I believe that we’ll get there – to the level where we can openly discuss SRM and people have more information to understand what SRM is.”

“The risks [of SRM] exist”, said Juan Pablo Letelier, “but there are more risks of not doing anything”.

Morning Takeaways

SRM101

Pete Irvine and Oliver Morton provided an introduction to SRM for newcomers to the field, addressing some of the most common questions about SRM: What is it? How much is necessary? Which methods could work best?

“You’d only need to reduce incoming sunlight by 1% to cool the planet by 1 degree”, said Irvine, adding, “Over time, you can use small adjustments to get on track to where you want to be. Just as we do with thermostats.”

Impacts modelling 1

Moderated by Godwin Ayesiga, four speakers covered the latest impacts modelling research on SRM, featuring a case study Inés Camilloni on Buenos Aires, Ping-Ping Narenpitak on mainland Southeast Asia, Romaric Odoulami on Africa, and Kelsey Roberts on marine ecosystems.

We unfortunately missed this session. If you have highlights, please reply and we'll note them in tomorrow's newsletter.

Atmospheric chemistry and physics

Speakers covered the challenging topics of stratospheric dynamics and aerosol microphysics in accessible terms, spurring an active discussion with the diverse audience. 

Sandro Vattioni noted, “I’ve never attended a conference on SRM where there are social sciences, government, media, physical sciences, where everyone meets and discusses. You could see from the questions that there are bridges constructed between the fields.”

The Climate Intervention Network for early career researchers

This session brought together early career researchers from across the world working in different disciplines to foster intergenerational dialogues and interdisciplinary collaboration. The conversation brought up the importance of community and highlighted common research challenges such as funding and the vulnerability of early career researchers working on controversial topics. The group also highlighted the importance of bringing more early career researchers into the field so they can help set the agenda for the broader field.

What can/can’t we learn from SRM modelling, from climate modeller and decision-making perspectives

Can modellers give policymakers the information they need to assess the potential impacts of solar geoengineering? It’s difficult, it emerged from a lively discussion featuring modellers (Simone Tilmes, Katharine Ricke, Lilia Xia) and policy experts (Andrew Light, Cedric Dzelu, Portia Adeleide Williams). What policymakers want to hear about is real world effects: how would SRM affect my agriculture, rainfall, or economic prospects? What would happen if things went wrong? Unfortunately – with the exception of SRM’s effect on heat – results are often too uncertain to provide clear answers. But that won’t stop modellers from trying: communicating about impacts that matter to policymakers is a rising focus in the field.

The status of stratospheric aerosol injection deployment technology

How could SAI be done? Leading experts (Hugo Wagner, Andrew Lockley, David Keith, Hugh Hunt, and Wake Smith) discussed what technologies would be required for potential deployments of SAI. Pre-existing technologies could go a long way and “there is no unobtanium”, according to Smith. Keith outlined a potential pathway to ramp up deployments, saying “you can start with existing aircraft… there’s not a big technological barrier to doing it”. Panellists agreed costs would not be a limiting factor, but there are practical challenges and serious governance and ethical questions to answer.

Afternoon Takeaways

SRM in climate models

Michael Taylor moderated the session focused on climate models – “indispensable tools” of SRM science. 

Given all the discussions of uncertainties, what can we say for certain about SAI? Daniele Visioni presented his answers to this question, reflecting on the behaviour of aerosols in the stratosphere. Claudia Wieners explored unilateral deployment and what it would take for countries to look beyond their own interests, also saying “it’s hard to weaponise SRM without turning the weapon against yourself”. Kwesi Quagraine presented improvements to model outputs through downscaling with regional refinement. Lastly, Colleen Golja discussed her team’s work on advancing a holistic risk assessment of SRM and other measures to address climate change.

Moving SRM governance forward

Portia Williams moderated a thought-provoking discussion of how to move SRM governance forward. The widely recognised Oxford Principles recommend that SRM should be governed as a global public good, but Xavier Landes presented a nuanced explanation of why the concept may not be a good fit for SRM. Bennett Francis then discussed the challenge of ensuring the legitimacy of SRM research, highlighting the importance of public involvement in this work. Lastly, Sven Schade took the discussion to the policy practicalities, explaining how the European Commission commissioned, and is looking to act on, recommendations for SRM and its research.

Targeted interventions: lessons in scaling, social license and field trials

How can research into targeted climate interventions move forward? In an interactive “fishbowl” panel discussion, the panelists (Marianne Hagen, Dante McGrath, Viktor Jaakkola, John Moore, Bridget Shayka, Ellen Haaslahti, Shaun Fitzgerald, and Benjamin Redmond Roche) fielded topics ranging from public and policymaker engagement to incorporating diverse indigenous perspectives. Ellen Haaslahti summarised much of the discussion, by stressing there needs to be a “balance between urgency and patience” when building trust and finding a path forward on targeted interventions.

International security implications of SRM

Could SRM lead to conflict between nations? Tyler Felgenhauer noted that SRM would not make a very good weapon, but scenarios can be imagined where international tensions rise due to the perception or expectation of impacts. On the other hand, if SRM reduced climate risks, could it be a force for peace? Scott Moore stressed it was time to think much more seriously about international rules of the road. Cynthia Scharf discussed the possibility of informal, back-door diplomacy on SRM between the US and China. Gwynne Dyer said he struggled, in practice, to think of a plausible scenario in which geoengineering deployment led to war.

Bridging science and policy in SRM: Latin America and the Caribbean’s role in future decision-making

Inés Camilloni invited participants to consider what the key questions are that policymakers need to make decisions. Continuing from Degrees Initiative workshops earlier in the week, Alia Hassan and Florencia Luna led an interactive discussion on the needs of different societal groups. The discussion covered the needs of multilateral organisations, the role civil society can play, what capacity may be required to prepare the region for the future, and how to promote inclusive, constructive conversations.

Film Screening: Plan C for Civilization

Filmmaker Ben Kalina held an advance screening of his upcoming documentary, Plan C for Civilization. The film quickly lays out the climate context and history of solar geoengineering concepts before focusing on the progress and challenges of SRM research efforts – through the lens of the SCoPEx project and its initiator David Keith, then parallelling the work of start-up Make Sunsets. Ultimately, the film raises the profile of SRM in an entertaining, accessible way that allows viewers to consider their own position.

In a Q&A following the screening, Kalina responded, “This is an unsettling topic. It really makes you question a lot. That is my goal.”

Wordle Time!

Thank you for reading. We'll be back tomorrow with highlights from Day 3.

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