1. This Week’s Top SRM Highlights
2. Research Papers
3. Web Posts
4. Reports
5. Book
6. Upcoming Events
7. Podcasts
8. YouTube Videos
Everything we publish on Solar Geoengineering Updates is free to access. If you value this work and are able, please consider supporting us as a paid subscriber. Your support sustains this vital work and helps us reach more people with balanced, timely information on this critical topic.
The International Risk Governance Council: Reflections on a 20-Year Experiment in Support of Improved Risk Governance
Authors: M. Granger Morgan, Marie-Valentine Florin, Igor Linkov, Kenneth A. Oye, Arthur C. Petersen, Ortwin Renn, Jonathan B. Wiener, Lan Xue
Synopsis: The International Risk Governance Council (IRGC), a Swiss nonprofit active from 2003–2023, advanced global understanding of emerging and systemic risks. Based in Geneva and later at EPFL Lausanne, it produced key reports and workshops on SRM, small modular reactors, synthetic biology, and resilience, highlighting the need for continued neutral risk governance.
Estimating high-resolution albedo for urban applications - Preprint
Authors: David Fork, Elizabeth Jane Wesley, Salil Banerjee, Vishal Batchu, Aniruddh Chennapragada, et al.
Synopsis: Researchers developed a method to enhance Sentinel-2 satellite albedo data from 10 m to 30 cm resolution using high-resolution imagery, enabling building-level mapping of cool roof potential. Validated over Boulder, CO (RMSE = 0.04), the approach applied to 12 global cities shows up to 0.5 °C urban cooling from full implementation, highlighting the policy value of prioritizing large buildings for effective heat mitigation.
Emerging hemispheric asymmetry of Earth’s radiation
Authors: Norman G. Loeb, Tyler J. Thorsen, Seiji Kato, Fred G. Rose, Øivind Hodnebrog, and Gunnar Myhre
Synopsis: Satellite data from 2000–2024 reveal a growing hemispheric imbalance in Earth’s energy budget, with the Northern Hemisphere absorbing 0.34 ± 0.23 W/m² per decade more solar radiation than the Southern Hemisphere. This “Earth darkening” is driven by aerosol, albedo, and water vapor changes, with limited cloud compensation—posing key implications for global circulation and future climate.
Geoengineering interventions in the Antarctic ice sheet: A potential solution to the effects of global warming, or a scientific utopia?
Authors: Pavel G Talalay, МА Sysoev
Synopsis: Antarctic ice loss, a major driver of sea-level rise, has tripled over the past 30 years. Researchers are exploring geoengineering interventions—such as altering ocean heat transfer, ice dynamics, or using solar radiation management—to slow melting. However, despite some theoretical progress, these approaches face major technical, environmental, and risk-related uncertainties, leaving glacier geoengineering far from ready for deployment.
Rapid Strategies to Slow Polar Sea-Ice Loss: A Technology Concept Note
Authors: Marcel Krüger
Synopsis: As polar sea ice loss accelerates, this concept note proposes near-term, small-scale, and reversible technologies to slow melting and stabilize seasonal ice. It defines quantitative targets, monitoring systems, ethics frameworks, and budgets, emphasizing that such interventions complement—not replace—emissions reductions.
Shortwave Absorption by Alumina Aerosol Amplifies Stratospheric Warming - Preprint
Authors: Taveen Singh Kapoor, Prabhav Upadhyay, Jian Huang, Guodong Ren, John Cavin, et al.
Synopsis: New measurements reveal that alumina aerosols, proposed for solar geoengineering and emitted by rockets, absorb more shortwave radiation than previously known. This absorption could offset up to 10% of alumina’s cooling effect and cause stronger stratospheric warming than black carbon, challenging assumptions about its climate safety.
Share Solar Geoengineering Updates
Inevitable & Obvious - The Architecture for Cooling Earth Is Finally Taking Shape
Frontiers - Solar geoengineering: growing scientific and political support for a non-use agreement
Good Men Project - What Are the Risks of Geoengineering to Fight Climate Change?
TCD - Researchers issue warning about ‘dangerous’ scheme to refreeze the Arctic: ‘Not feasible’
University of Chicago - CSEi Welcomes its Inaugural Cohort of Research Fellows
Earth.Org - Bering Strait Dam Proposal to Save AMOC Reignites Geoengineering Controversy
Medium - Cool the Planet, Fry the Future: The Trap of Solar Geoengineering
Grist - So many climate solutions, so few emissions reductions. A new book explains why
Politico Pro - Refreeze the Arctic? Scientists split over polar geoengineering
TCD - Researchers sound alarm over controversial plan to block ocean currents: ‘Unlikely to be socially acceptable’
Energy News - French Academy of Sciences warns of economic risks linked to solar geoengineering
LinkedIn - Geoengineering, Evidence, and the Ethics of Refusing to Know
SRM360 - Scientists Divided Over Polar Geoengineering Study
The Rogue Scholar - Manipulating the global thermostat
Share
Institute of France - Climate Geoengineering: Scientific State of Play, Challenges, and Outlook
Andreas Malm and Wim Carton - The Long Heat: Climate Politics When It’s Too Late
6 – 9 October | Online - Virtual workshop series on Stratospheric Aerosol Injection
09 October | United States - Expanding the Toolbox for a Safe, Equitable Climate Future by Manny’s (NEW)
09 October | United States - Geoengineering, Global Warming & Sunlight Reflection Methods by Manny’s
Saturdays 11 October - 22 November 22 | Online & In-person - An Intro to Climate Systems Engineering by Members of the Climate Systems Engineering Initiative (including David Keith, Tiffany Shaw, and B.B. Cael)
14 October | Online - Exploring governance analogues for SRM research by Co-Create (NEW)
15-16 October | Online - Conference: The Global Heating Emergency Preventing 2°C by 2040: What’s the Plan? by Healthy Planet Action Coalition
16 October | UK - Discover Climate Repair: another kind of climate action by Centre for Climate Repair (NEW)
17 October - Introducing SkyScroll by Planetary Sunshade Foundation
21-22 October | Helsinki, Finland - Workshop: The Future of climate intervention research - an early career gathering by Alliance for Just Deliberation on Solar Geoengineering
23 October | Helsinki - ATLAS25: Risk Management of Earth System Tipping Points by Operaatio Arktis
24 October | Finland - Climate Reckoning: Dr James Hansen & Clare Farrell on where we really stand by Operaatio Arktis (NEW)
3-7 November | Pune, India - 11th WMO Scientific Conference on Weather Modification
15-19 December | New Orleans, Louisiana - 2025 American Geophysical Union Meeting
9-13 March 2026 | Kyoto, Japan - CMIP Community Workshop (CMIP26)
21-26 June 2026 | United States - Gordon Research Conference - Bridging Observations, Models, and Impacts in Solar Radiation Modification Research
Solar Geoengineering Events Calendar
The Science of Geoengineering – with Dr. Zeke Hausfather | Green Street, The Environmental Health Show
“Dr. Zeke Hausfather talks about his work on climate change and the various kinds of solutions being proposed to reduce the intensity of solar heating while we simultaneously reduce our dependence on fossil fuels.”
SRM hoses - Hyde | Reviewer 2 does geoengineering
 | SRM hoses - Hyde Reviewer 2 does geoengineering 43:38 |
“Roderick Hyde discusses his recent paper on using high-altitude hoses for solar geoengineering. While most proposals focus on aircraft delivery, Hyde revisits an older but largely dismissed concept. He describes suspending a 20 km hose by balloons to continuously pump sulfur-bearing fluids into the stratosphere, and argues that advances in modern materials and engineering may overcome past barriers.
The conversation covers the technical hurdles such as wind dynamics, hose stability, extreme pressures, and material stress, as well as design variations for pumping H₂S as liquid or gas. Hyde explains how streamlining, intermediate pumps, and lightweight aero-shrouds could make the system viable.
The discussion also highlights the potential advantages of this approach, including affordability, continuous operation, and scalability. While a single hose could not halt global warming, Hyde suggests that a distributed network of ~20 installations could offset warming from CO₂, offering a near-term, low-cost option to buy time while longer-term climate solutions take effect.
Paper: Hyde, R. A. (2025). A Planetary Cooling Hose. arXiv preprint arXiv:2509.07985. https://doi.org/10.48550/arXiv.2509.07985“
More Moore - polar SRM research | Reviewer 2 does geoengineering
 | More Moore - polar SRM research Reviewer 2 does geoengineering 56:12 |
“John Moore joins the podcast to discuss his recent Viewpoint article responding to Siegert et al.’s paper on polar geoengineering. While Siegert and colleagues argue that proposed interventions are infeasible, environmentally dangerous, and a distraction from decarbonization, Moore contrasts the prevailing “consequences-based paradigm” (raising alarms to spur actions) with a new “compassionate harm reduction paradigm” that calls for exploring all potential tools including geoengineering rather than rejecting them outright, so humanity has options to reduce harm if warming overshoots.
The conversation covers the risks of melting glaciers and sea-level rise, and specific concepts such as stratospheric aerosol injection. Moore also stresses the importance of Arctic Indigenous leadership, pointing to Saami Council-led review processes as a model for rights-based and knowledge co-produced governance.
The discussion also highlights the sharp divides in the climate community over polar geoengineering and raises fundamental questions about the responsibilities of scientists in an era of accelerating climate risk.
Papers:
Lead Article: Siegert, M., Sevestre, H., Bentley, M. J., Brigham-Grette, J., Burgess, H., Buzzard, S., ... & Truffer, M. (2025). Safeguarding the polar regions from dangerous geoengineering: a critical assessment of proposed concepts and future prospects. Frontiers in Science, 3, 1527393. https://doi.org/10.3389/fsci.2025.1527393
Viewpoint: Moore, J. C., Macias-Fauria, M., & Wolovick, M. (2025). A new paradigm from the Arctic. Frontiers in Science, 3, 1657323. https://doi.org/10.3389/fsci.2025.1657323“
To Capture the Present Moment, You Either Write Historical Fiction or Science Fiction: Interview with Kim Stanley Robinson, Part 2 | Toke Lykkeberg
Grappling with accelerating climate risks | Euractiv
“Join this Euractiv Hybrid Conference for a discussion on the scientific, ethical, and political dimensions of Solar Radiation Modification research. Together with leading experts and policymakers, we’ll explore:
-What is SRM, what might it offer in the future, and why is it so controversial?
-Could SRM shift global power dynamics, and how can the EU position itself to lead in shaping global rules and safeguards?
-Where are the biggest knowledge gaps and how can public research help fill them, transparently and ethically?
-What would responsible SRM research look like?
-How do we get it right for future generations, ensuring that today’s decisions don’t create tomorrow’s regrets?”
Solar Geoengineering is up to 14X More Efficient than CDR: The Global Albedo Oversight Crisis | Innovinc Conferences
Time Left Estimates to Critical Feedback/Loops: Proposed Annual Solar Geoengineering IPCC | Innovinc Conferences
Making Sense of Sea Ice and Solar Geoengineering | SRM360
“An expert panel explores:
– How climate change is contributing to sea ice decline
– The impacts of sea ice loss on climate, ecosystems, and communities
– Potential adaptation strategies in a changing Arctic and Antarctic
– Whether solar geoengineering could help slow sea ice loss
– Broader challenges and considerations raised by solar geoengineering”
Nature-based Ocean and Atmospheric Cooling (NOAC) | Clive Elsworth
Geoengineering is coming - Wake Smith | AARES/ARE-UWA
Geoengineering: a Technofix for the Climate? | Claudia Wieners | Jeroen Oomen | Studium Generale Maastricht University
“During this double lecture, two speakers will explore the theme of geoengineering from different perspectives. Each talk lasts approximately 30 minutes. Afterwards, there will be an opportunity for questions and discussion with the audience.”
Climate Change: Why It Is Not Too Late—Chris Field | notredamebusiness
“Climate Change: Why It Is Not Too Late
Plenary by Chris Field, Perry L. McCarty Director of the Stanford Woods Institute for the Environment at Stanford University”
Common Ground Episode 6: Geoengineering - Good or Bad | Navigating Carbon
“In this conversation, Deb Ryan and Teresa Hartmann discuss the complexities of geoengineering, including its governance, ethical implications, and the various technologies proposed to combat climate change. They explore the differences in state regulations regarding climate manipulation, the risks associated with solar radiation management, and the importance of addressing the root causes of climate change rather than relying on quick fixes. The discussion also touches on the regulatory challenges faced by emerging technologies in the carbon market and the need for a nuanced understanding of acceptable risks in climate solutions.”
Follow us on:
Twitter | Bluesky | YouTube | Substack | Google Group | Podcast 1 | Podcast 2
Support us here:
While all content on Solar Geoengineering Updates is free for everyone, I invite those who can to become paid subscribers. Your support empowers this important work and helps us spread the message far and wide.
Share Solar Geoengineering Updates
