1. This Week’s Top SRM Highlights
2. Research Papers
3. Web Posts
4. Reports
5. Podcasts
6. YouTube Videos
7. Upcoming Events
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RESEARCH PAPER: Reduced aerosol pollution diminished cloud reflectivity over the North Atlantic and Northeast Pacific (Nature Communications)
TWEET: Elon Musk proposes AI satellite shield to fight climate change by dimming the Sun (Interesting Engineering)
REPORT: Solar radiation modification (The Royal Society)
NEWS: Geoengineering startup has been secretly lobbying Congress for months (Politico Pro)
PODCAST: Distributing solid aerosols - Hack (Reviewer 2 does geoengineering)
CONFERENCE RECORDING: The Global Heating Emergency Preventing 2°C by 2040: What’s the Plan (Healthy Planet Action Coalition)
EVENT: COP30 Brasil Amazonia | Belem (COP30)*
*Some of the SRM events taking place at COP30 are listed in the “Upcoming Events” section below
Read on to unpack more updates:
Analysis of Space-Based Infrared Shielding as the Solar Radiation Protections for Global Warming Mitigations
Authors: Kyung Bae Jang, Tae Ho Woo
Synopsis: This system dynamics study models how SRM could reduce global warming by reflecting sunlight, especially infrared. Simulations show gradual mitigation, with shielding placement and angle affecting outcomes. Comparing two spatial configurations, Case 2 achieved stronger cooling, highlighting the importance of optimal positioning. Results suggest SRM can lower temperatures but doesn’t address greenhouse gas causes. Further work should refine shield placement for greater effect.
Stratospheric aerosol climate intervention could reduce crop nutritional value
Authors: Clark, Brendan, Alan Robock, Lili Xia, Sam S. Rabin, Jose R. Guarin, and Jonas Jägermeyr
Synopsis: Stratospheric aerosol intervention cools the planet by adding sulfate to the stratosphere, decoupling temperature from CO₂. In this study, crop-model simulations show that holding warming to 1.5 °C with SAI reduces global protein concentrations in maize and rice, with little change in wheat and soybean. This could worsen protein scarcity in already vulnerable, diet-dependent regions. Model spread underscores the need for more crop models, climate scenarios, and improved protein response representation.
Macroclimate growing conditions for luxury crops after stratospheric aerosol injection
Authors: Ariel L Morrison, Elizabeth A Barnes, James W Hurrell and Daniel M Hueholt
Synopsis: Climate change threatens luxury crops like grapes, coffee, and cacao through heat and shifting rainfall, with natural variability amplifying year-to-year losses. Comparing ensemble simulations with and without SAI, researchers find that although SAI cools temperatures, it does not consistently preserve favorable growing conditions. Variable precipitation and humidity drive a wide range of outcomes, improving conditions in only 6 of 18 regions. Disease risk reduction helps where gains occur. Revenue impacts vary widely, and results depend strongly on the chosen SAI temperature target.
Spaces of anthropogenic CO2 emissions compatible with climate boundaries
Authors: Thomas Bossy, Philippe Ciais, Katsumasa Tanaka, Franck Lecocq, Philippe Bousquet & Thomas Gasser
Synopsis: Climate boundaries define safe limits for global warming, ocean acidification, sea-level rise, and Arctic ice loss. A reduced-form model explores CO₂ emissions, removal, and SRM pathways that stay within these limits. With emissions peaking in 2030, net-zero by 2050, and 10 PgC yr⁻¹ removal, there’s an 80% chance of keeping warming below 2 °C without SRM, but only 35% when all four boundaries are combined, revealing trade-offs and the need for holistic strategies.
Reduced aerosol pollution diminished cloud reflectivity over the North Atlantic and Northeast Pacific
Authors: Knut von Salzen, Ayodeji Akingunola, Jason N. S. Cole, Ruth A. R. Digby, Sarah J. Doherty, et al.
Synopsis: Observations show marine cloud reflectivity in the North Atlantic and Northeast Pacific fell by ~2.8% per decade from 2003–2022, increasing ocean heat uptake. Most Earth System Models underestimated this decline and related warming, but an improved aerosol–climate model matched observations. Reduced sulfur dioxide and aerosol precursors explain ~69% of the change. Continued emission cuts may further weaken cloud reflectivity, suggesting near-term climate projections may need revision.
Sunburned plankton: ultraviolet radiation inhibition of phytoplankton photosynthesis in the Community Earth System Model version 2
Authors: Joshua Coupe, Nicole S. Lovenduski, Luise S. Gleason, Michael N. Levy, et al.
Synopsis: Increased UV harms marine phytoplankton. A modified CESM2-UVphyto model simulates UV inhibition and penetration in the ocean. Simulations show deeper biomass and productivity, moderate global productivity decline, and shifts in community structure. The model helps assess biogeochemical and ecosystem impacts from ozone-disrupting events including asteroids, volcanoes, nuclear war, and stratospheric aerosol injection.
Climate Governance State of Art: A Snapshot on Current Discussions on Solar Radiation Management - Conference Paper
Authors: Yvette Ramos
Synopsis: Climate governance encompasses legal and non-legal rules, norms, and institutions that guide responsible technology development, risk analysis, and policy incentives. SRM seeks to reflect sunlight to reduce warming, while the International Space Weather Initiative (ISWI) monitors solar activity affecting Earth. ISWI data can inform SRM methods like stratospheric aerosol injection, and monitor potential impacts. The paper highlights how ISWI could strengthen governance and oversight of SRM.
Reply to Comment by Strawa et al. (2025) on Webster and Warren (2022): “Regional Geoengineering Using Tiny Glass Bubbles Would Accelerate the Loss of Arctic Sea Ice”
Authors: Stephen G. Warren, Melinda A. Webster
Synopsis: A 2018 idea to spread white glass powder over Arctic sea ice aimed to boost sunlight reflection. Modeling suggested it brightens bare, thin ice but darkens snow-covered ice due to light absorption. New measurements show lower absorption (2.5% vs. 10%), yet field tests still find weaker brightening than expected. This gap between models and experiments highlights uncertainties in reflective surface geoengineering.
Solar Geoengineering Updates - Monthly Solar Geoengineering Updates (October’2025)
The Degrees Initiative - Four new countries begin SRM research through Degrees’ funding
MIT Technology Review - Why the for-profit race into solar geoengineering is bad for science and public trust
Interesting Engineering - Elon Musk proposes AI satellite shield to fight climate change by dimming the Sun
The Degrees Initiative - Degrees-funded scientists reach 50-paper milestone in solar geoengineering research
Carnegie Endowment for Int’l Peace - Bipartisan Backlash Against Geoengineering and Carbon Removal in the United States
Security In a Warming World! - The $60 Million Solar Geoengineering Bet
Politico Pro - Geoengineering startup has been secretly lobbying Congress for months
Phys.Org - Climate intervention may not be enough to save coffee, chocolate and wine
The Guardian - Solar geoengineering in wrong hands could wreak climate havoc, scientists warn
WeathEire - Fewer aerosols, faster warming, study warns
Graphic Online - Dr. Kwesi Quagraine warns: ‘Africa must be at the table in climate engineering decisions’
The Royal Society - Solar radiation modification could reduce global temperatures but is no substitute for reducing emissions, says Royal Society
Newsroom - Climate Intervention Techniques Could Reduce the Nutritional Value of Crops, New Study Finds
The Times - Six radical ways we could cool the planet
E&E News - UK science academy sees promise in solar geoengineering — but not as sole climate fix
Oceanographic Magazine - Why are polar experts taking a stand against geo-engineering?
NERC - Policy Brief: Safeguarding the polar regions from dangerous geoengineering
Georgetown University - Governing India’s Geoengineering Attempts: An ISD International Negotiation Simulation
The Palm Beach Post - ‘Chemtrail’ crackdown: Florida law has PBIA seeking evidence of weather conspiracy
Zero Geoengineering - Pennsylvania Senator Calls on Trump Administration to Defund SRM Programs
Happy Medium - Turning Back The Planet’s Clock
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The Royal Society - Solar radiation modification
Synopsis: Solar radiation modification could reduce global temperatures but is no substitute for reducing emissions.
The Sunlight Managers w/ Sofia Menemenlis | Politics Theory Other
“Sofia Menemenlis joins PTO to chat about her recent article in The Breakdown on the concept and history of solar geoengineering - or “solar radiation management” as it has become known. We talked about how the implementation of SRM is imagined, what the potentially catastrophic side effects of such a project might be, and who the key players are in terms of research and potential deployment of the technology.”
“Geoengineering: the good, bad and the ugly of this ‘break glass in case of emergency’ fix” | Quirks and Quarks
“Claudia Wieners and Julienne Stroeve tell us about the pros and cons of genengineering.”
Distributing solid aerosols - Hack | Reviewer 2 does geoengineering
 | Distributing solid aerosols - Hack Reviewer 2 does geoengineering 59:57 |
“Miranda Hack provides an in-depth look at the often-overlooked engineering and logistical barriers to large-scale deployment of solid particles for stratospheric aerosol injection (SAI). She explains how dispersing sub-micron mineral particles at altitude, including challenges like agglomeration, complex nozzle flows, and supply-chain constraints, introduces significant uncertainties and costs. These challenges may reduce cooling efficiency and narrow the design space for “low-risk” SAI strategies, suggesting that solid aerosols could be far less viable than existing models assume.
Paper: Hack, M., McNeill, V. F., Steingart, D., & Wagner, G. (2025). Engineering and logistical concerns add practical limitations to stratospheric aerosol injection strategies. Scientific Reports, 15(1), 34635. https://doi.org/10.1038/s41598-025-20447-2”
International Law and Climate Interventions: Is There a There There? | The Salata Institute at Harvard University
“Daniel Bodansky, Regents’ Professor of Law at the Sandra Day O’Connor College of Law at Arizona State University, presents as part of Salata’s Solar Geoengineering Research Seminar series.”
What’s Up with COP30 | Climate Emergency Forum
“In this candid forum, our panelists explore the lack of democratic participation in COP processes, the dominance of special interests, and the rising tide of climate impacts worldwide. Personal experiences from recent conferences highlight both the logistical hurdles and the morale-boosting power of these global gatherings. The conversation addresses not only the political and financial roadblocks to climate action but also raises vital questions about the future of these conferences, the role of technology in fostering global participation, and the urgent need for innovative solutions—such as large-scale carbon removal and advanced cooling techniques.”
Conference: The Global Heating Emergency Preventing 2°C by 2040: What’s the Plan | Healthy Planet Action Coalition
“In Paris in 2015, 195 countries committed to stopping global warming. But greenhouse gas emissions have continued to relentlessly increase.
The latest science shows that instead of slowing down, temperatures are now rising at twice the rate of previous decades. At this pace, the Paris Accord’s critical red line of 2°C is likely to be breached by 2037—just 12 years from now.
The Healthy Planet Action Coalition (HPAC) brought together scientists, policymakers, and concerned citizens for a global online conference to build awareness about why temperatures are accelerating, and what this means for humanity. We sought to create momentum for a more comprehensive global action plan to address the new realities that we are facing before it’s too late.
We are nearly out of time to avert 2°C. But, there are tools in the toolbox that can buy more time to successfully stop global heating in the short term, while we strive to bring down emissions in the medium to long term.”
SRM research in Morocco: Assessing temperature and rainfall extremes | The Degrees Initiative
“Researchers in Morocco, Cabo Verde, Jordan and the Republic of the Congo have been awarded Degrees Initiative funding, embarking on their countries’ first studies on solar radiation modification (SRM).
In this short video, we meet the new Morocco team as they begin examining how SRM could influence rainfall and temperature extremes across North Africa. Led by Dr Victor Ongoma of Mohammed VI Polytechnic University, the project addresses a critical regional challenge:
-North Africa is warming at twice the global rate, placing pressure on communities that rely heavily on climate-sensitive sectors such as rain-fed agriculture.
-The team reflects on the limits of adaptation, the urgency of understanding SRM’s potential impacts, and the importance of African-led research in shaping future climate decisions.”
SRM research in Jordan: Climate impacts on agriculture and water scarcity | The Degrees Initiative
“Researchers in Jordan, Cabo Verde, Morocco and the Republic of the Congo have been awarded Degrees Initiative funding, embarking on their countries’ first studies on solar radiation modification (SRM).
In this short video, we meet the new Jordan team as they begin investigating how SRM could influence crop productivity in one of the world’s most water-scarce regions. Led by Prof. Jawad Al-Bakri from the University of Jordan, the project examines how SRM could interact with existing agricultural adaptation strategies under extreme arid conditions.
The team reflects on why locally grounded research is essential, how water scarcity shapes Jordan’s vulnerability, and why understanding the full picture of climate impacts matters for future food and water security.”
SRM research in the Republic of the Congo: Upwelling systems and coastal resilience | The Degrees Initiative
“Researchers in the Republic of the Congo, Cabo Verde, Jordan and Morocco have been awarded Degrees Initiative funding, embarking on their countries’ first studies on solar radiation modification (SRM).
In this short video, we meet the new team from the Republic of the Congo as they begin exploring how SRM and global warming could shape the Congolese Upwelling System, an essential source of nutrients for coastal fisheries and a foundation of local food security. Led by Roy Dorgeless Ngakala, the project will assess how regional coastal ecosystem health could change under different climate and SRM scenarios.
The team reflects on why understanding these shifts is vital for fisheries and future climate planning, and how locally led research can better inform scientists and policymakers across the Gulf of Guinea.”
SRM research in Cabo Verde: Understanding extreme weather risks | The Degrees Initiative
“Researchers in Cabo Verde, Jordan, Morocco and the Republic of the Congo have been awarded Degrees Initiative funding, embarking on their countries’ first studies on solar radiation modification (SRM).
In this short video, we meet the new Cabo Verde team as they prepare to explore how SRM could influence extreme weather on Santiago Island. Led by Dr Patrik Pina da Silva from the University of Cape Verde, the project will examine how changes in precipitation and temperature could affect a small island nation already facing rising heat, shifting rainfall patterns and increasing drought.
The team reflects on why locally led research matters, how Cabo Verde’s unique climate systems shape vulnerability, and why building knowledge is essential for informed decision-making.”
Human Solar Dimming Efforts And Geoengineering - 11.3.25 PRE Education Meeting | Brendan Moore, PhD
“This webinar video is of Richard Troy, Chief Scientist of Science Tools Corp., covering an excerpt from a 33-page scientific paper, “Evaluation of Plausible Choices for Human Solar Dimming Efforts,” which rigorously examines the concept of Solar Radiation Management (SRM) as a temporary climate change solution. The author, Richard Troy, argues that while SRM, involving the intentional insertion of aerosols into the atmosphere to dim the sun, is a “terrible idea,” it may be necessary given the inadequate global response to warming. The core of the paper is a detailed ranking and analysis of fifteen plausible aerosol candidates, such as calcium carbonate, crushed basalt, and silica, evaluating their effectiveness, environmental impacts (like acid rain or toxicity), and lofting challenges. Crucially, the paper insists that any dimming effort must be paired with aggressive global decarbonization and carbon removal to be anything more than a short-term failure, noting that SRM will inevitably reduce the efficiency of solar and wind power generation, creating a complex moral and strategic dilemma for energy systems.”
10-21 November | Belem - COP30 Brasil Amazonia (NEW)
Some SRM-related events at COP30:
13 November | University of Cambridge & Online - Discover Climate Repair: Discover Possibilities by Centre for Climate Repair (NEW)
13 November | New York - Documentary Plan C For Civilization World Premiere
14 November | Online - Planetary Sunshade Foundation - annual update by Planetary Sunshade Foundation
14 - 30 November | Online - Documentary Plan C For Civilization World Premiere
15 November | New York - Documentary Plan C For Civilization World Premiere
01 December | Online & In-person (UK) - Good COP, Bad COP: First reflections on COP30 by Centre for Climate Repair
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
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