Weekly Solar Geoengineering Updates (20 July - 26 July 2026)
Weekly SRM roundup of research papers, web posts, events, jobs, projects, podcasts, videos and much more.
JUMP TO SECTION
1. This Week’s Top SRM Updates
2. Research Papers
3. Web Posts
4. Reports
5. Upcoming Events
6. Podcasts
7. YouTube Videos
THIS WEEK’S TOP SRM HIGHLIGHTS
Research Paper: Cool cities, local contexts: A typology of cooling interventions across the disciplines to address extreme heat and decarbonization in urban areas (ScienceDirect)
Preprint: Tracing vessel-generated sea spray aerosols to support marine cloud brightening (EGUSphere)
Report: The Case Against Blanket Bans: A State Permitting Model for Solar Radiation Management (University of Houston Law Center)
News Article: Heatwaves caused by fall in pollution (The Telegraph)
News Piece: Trump ally floats Republican pitch for sun-blocking technologies (E&E News by Politico)
Podcast: Is geoengineering a security threat? (The Land & Climate Podcast)
YouTube Video: SRM Governance, Ethics & Africa’s Role in Global Decision-Making (Emerging Climate Frontiers)
Read on to unpack more updates:
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RESEARCH PAPERS
Authors: William McFarlane Smith, Daniele Visioni, Ben Kravitz, Evelien van Dijk, Trude Storelvmo and Hugh Hunt
Synopsis: A GeoMIP study tested cirrus cloud thinning (CCT) in four Earth System Models by increasing the fall speed of ice crystals under the high-emissions SSP5-8.5 scenario. All models projected global cooling of 0.42–0.93°C by mid-century and increased precipitation, as thinning cirrus clouds allowed more heat to escape to space. However, large differences in lower-cloud, humidity, and hydrological responses highlight major uncertainties and the need for better cirrus cloud representation.
Leveraging transfers to strengthen climate cooperation under the threat of solar geoengineering
Authors: David M. McEvoy, Matthew McGinty
Synopsis: Researchers investigate how financial transfers within international environmental agreements (IEAs) could reduce reliance on solar geoengineering (SGE). Their model shows that transfers can strengthen cooperation on emissions reductions, expand the number of stable agreements, improve overall efficiency, and indirectly limit potentially harmful SGE deployment by encouraging greater global climate mitigation.
Authors: Benjamin K Sovacool
Synopsis: Researchers present a case study of the Mirrors for Earth’s Energy Rebalancing (MEER) project in Freetown, Sierra Leone, which uses reflective mirrors and recycled PET bottle furniture to reduce urban heat exposure in vulnerable communities. Drawing on site visits, interviews, and document analysis, the study evaluates this RM approach as a potential low-cost intervention for extreme heat in a city where limited electricity access makes air conditioning largely unavailable.
Challenges and Opportunities of Solar Geoengineering for Climate Governance
Authors: Furini, Francesco ; Finus, Michael
Synopsis: This review examines the governance challenges associated with the potential deployment of solar geoengineering, focusing on the strategic incentives it creates for nations. It explores theoretical models of the "free-driver problem"—where one or a few countries could deploy the technology without global consent—and assesses how interactions between solar geoengineering and emissions mitigation could shape future international climate governance.
Authors: Melissa A Martin, Benjamin K Sovacool
Synopsis: A new review proposes a typology of local cooling interventions for tackling extreme heat, grouping strategies into four categories: lowering temperatures, modifying buildings, changing human behavior, and decarbonizing energy systems. Drawing on research across multiple disciplines, the study highlights how climate mitigation, adaptation, infrastructure resilience, and geoengineering can complement one another, emphasizing the need for integrated approaches to address rising urban temperatures.
Tracing vessel-generated sea spray aerosols to support marine cloud brightening - Preprint
Authors: Xiaoshen Sun, Chris Medcraft, Ramon Braga, Peter Butcherine, Zoran Ristovski, Steven Siems, Christian J. Sanders, and Daniel P. Harrison
Synopsis: Scientists developed a new airborne "tracer" method to detect and track aerosols released during MCB experiments over Australia's Great Barrier Reef without using chemical tracers. By distinguishing sea spray aerosols from combustion exhaust, the technique reliably tracked MCB aerosol plumes across 14 research flights, providing a valuable tool for studying aerosol transport and assessing how MCB influences marine clouds and coral reef cooling.
WEB POSTS
The Cooler - Much ado about geoengineering
Climate Trunk - Why Earth is reflecting less of the Sun’s energy
GNA - Experts call for African voice in solar geoengineering debate
NASA - Dimming the Sun (DimSun) Using Controllable Dust Cloud to Reduce Solar Insolation
Upon Further Reflections - Sunlight reflection options: a quick primer (and why Reflective prioritizes SAI)
University of Houston Law Center - New UH Law Center Report Offers Safe Permitting Model as States Weigh Counterproductive Legislation on Solar Radiation Management Research
ScienceDirect - Letter to the editor: Rethinking expertise on climate cooling technologies
African Tech Futures Lab - Selling Stability: The Problem with Pitching “Climate Stabilization” as a New Category of Climate Response
Everything and the Carbon Sink - Uncomfortable bedfellows: carbon removal and solar radiation management
The Telegraph - Heatwaves caused by fall in pollution
Carbon Brief - Factcheck: No, Europe’s heatwaves are not being ‘caused’ by declining air pollution
Scottish Government - Confirmation and Records of Geoengineering and Solar Radiation Modification (SRM) activities over Scotland: EIR release
Nature - Can giant space mirrors boost green energy on Earth? A start-up aims to find out
New Scientist - Cloudy skies have slowed global warming – but that may be changing
E&E News by Politico - Trump ally floats Republican pitch for sun-blocking technologies
Reef Ranch - Reef Digress: Broadening the Boundaries of Human Intervention: Blind Alleys and Groundbreaking Ideas
REPORTS
University of Houston Law Center - The Case Against Blanket Bans: A State Permitting Model for Solar Radiation Management
Renaissance Philanthropy - Building Permission Space & Narrative Framing for Climate Stabilization
UPCOMING EVENTS
31 July | Online - Climate Intervention Virtual Symposium (NEW)
01 September | Online - Beyond the Headlines: Reporting on Solar Geoengineering by Solution Journalism Network
10-11 September | Washington, DC. - 2026 RFF and Harvard SRM Social Science Research Workshop
12-15 October | Malaysia - Global Tipping Points 2026 | Abstract Deadline: 15 May
7–11 December 2026 | San Francisco, CA - AGU26 Anuual Meeting | Abstract Submission Deadline: 05 August 2026
10-14 January 2027 | Denver, CO & Online | 19th Symposium on Aerosol–Cloud–Climate Interactions
08-09 April 2027 | United States - 2027 Solar Radiation Management Annual Meeting by Simons Foundation
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PODCASTS
Is geoengineering a security threat? | The Land & Climate Podcast
“Geoengineering research is growing, as scientists look for increasingly radical means to protect humanity from the disastrous impacts of global heating.
Less publicly, concerns are also building about the use of these techniques for geopolitical disruption or control.
Technologies such as solar radiation management (SRM) and stratospheric aerosol injection (SAI) are controversial amongst climate scientists: they could buy us time through a temporary cooling effect, but they would not actually stop global heating, and could cause other negative impacts.
Danielle Young tells Alasdair that scientific research on these technologies often lacks alignment with political realities. While scientists plan for multilateral governance regimes to protect global populations from heat, government and military officials are more likely to think about SRM or SAI in terms of weaponisation and international power struggles.”
YOUTUBE VIDEOS
The Albedo Imperative | ToSaveTheWorld
“Robbie Tulip and Gene Fry discuss how declining planetary albedo, primarily due to cloud loss, accelerates climate warming, necessitating urgent albedo restoration alongside carbon removal efforts.”
Have we entered a New Normal? Tom Harris | Cybernetics Society
“Have we entered a New Normal? The physics, the feedbacks, the implications and the responses to our changing climate
The talk walks through the physics of climate change using the very latest satellite data to show how the planet is out of energy balance, is accumulating energy at an accelerating rate, and how this energy is taken up as heat in different Earth systems.
The up-coming ‘Goliath’ El Niño effects will be looked at with reference to past events and the phenomenon of temperature ratcheting uncovered, leading to predictions for the second half of this decade. Tipping points are the next topic, focussing on the ocean currents and Amazon rainforest, as well as the economic consequences of the continued warming.
The talk then looks at the triad of measures we still have available to combat the predicament — decarbonising the economy, removing greenhouse gases from the atmosphere, and deploying solar geoengineering.
Finally we try and answer the question of whether this is a new normal.”
Climate Intervention: Funding Impact Assessments | Climate Emergency Forum
“In this episode we introduce the Climate Intervention Environmental Impact Fund (CIEIF), a unique family-funded initiative that supports climate intervention field tests by financing rigorous environmental impact assessment and stakeholder outreach. Fund manager and environmental attorney Peter Jenkins and science advisor Dr. Renaud de Richter explain how the fund focuses on projects with real-world field trials that can scale to meaningful climate benefits, rather than basic research or conventional adaptation and clean energy efforts.”
SRM Governance, Ethics & Africa’s Role in Global Decision-Making | Emerging Climate Frontiers
“Join us for an insightful webinar on the governance, ethics, and global policy considerations surrounding Solar Radiation Modification (SRM), with a special focus on Africa’s voice in shaping international climate decisions. The session will be led by Prof. Samuel Essien Baidoo, Associate Professor of Laboratory Medicine and Fellow of the West African Postgraduate College of Medical Laboratory Science, who will share expert perspectives on the opportunities, challenges, and ethical questions surrounding emerging climate intervention technologies.”
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Another gem from Andrew. Gotta alot of reading to do. Just the first 2 line items ( cool cities and sea sprayers ) got me in higher gear.