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RESEARCH PAPER: Simulated Climate and Carbon Cycle Response to Arctic Ocean Albedo Modification (AGU)
PREPRINT: Solar Radiation Modification is projected to increase land carbon storage and to protect the Amazon rainforest (EGUSphere)
REPORT: Climate geoengineering: call for caution and rigorous supervision (French Academy of Sciences)
WEB POST: It’s a bird! It’s a plane! It’s a chemtrail? A new conspiracy theory finds traction at Kennedy’s HHS (CNN Health)
JOB OPPORTUNITY: Engagement Coordinator (Centre for Climate Repair)
LECTURE: Climate as a 4D Problem - Featuring David Keith (UChicago Climate Systems Engineering initiative)
Read on to unpack more updates:
Opium for the Earth at the expense of nonhuman animals? Geoengineering and interspecies justice
Authors: Leonie N. Bossert
Synopsis: This article argues that ethical debates on geoengineering overlook the impacts on nonhuman animals. It calls for a non-anthropocentric perspective, integrating animal well-being into discussions of climate justice. Highlighting gaps in research, it urges studies comparing animal welfare under geoengineered versus non-geoengineered climates and exploring political representation for animal interests. The piece also reflects on interspecies justice in the context of marine cloud brightening, promoting broader ethical inclusion in climate intervention debates.
Investigation of Ship-Induced Mesoscale Circulation Mechanics and Aerosol Plume Spreading Rates
Authors: Lucas A. McMichael, Peter N. Blossey, Robert Wood, Sarah J. Doherty
Synopsis: Aerosol plumes from ships can brighten low clouds, but the extent depends on how the plume spreads. Using large-eddy simulations of stratocumulus clouds, researchers found that droplet sedimentation and collision-coalescence mainly control plume buoyancy and spreading, while droplet size has little effect. These insights help improve climate model parameterizations and inform Marine Cloud Brightening feasibility assessments.
Evaluation of climate intervention technologies for sustaining cities close to oil and gas operations: A sustainability and feasibility-based decision support system under molecular fuzzy set
Authors: Abdolvahhab Fetanat, Mohsen Tayebi
Synopsis: To tackle worsening environmental extremes in southern Iran, researchers developed an intelligent Decision Support System using the Delphi-fuzzy molecular ranking (DFMORAN) model to assess ten climate intervention technologies, including SRM methods such as SAI, space-based geoengineering, and MCB. Evaluating 17 sustainability and feasibility criteria, the study found afforestation and reforestation and soil carbon sequestration to be the most effective and sustainable options, while SRM approaches showed potential for short-term climate moderation but with higher feasibility and governance challenges.
A Risk-Risk Assessment of Climate Extremes: Comparing Greenhouse Gas Warming and Stratospheric Aerosol Injection in UKESM1
Authors: Alice F. Wells, James M. Haywood
Synopsis: Using the UKESM1 model and GeoMIP’s G6controller scenario, this study assesses SAI as a solar climate intervention to counteract greenhouse gas–driven extremes under SSP5-8.5. The multi-latitude G6controller strategy lowers global temperatures to SSP2-4.5 levels, significantly reducing heat, precipitation, and fire extremes, particularly in Europe, South America, and southern Africa, without causing new drying patterns. Findings underscore SAI’s potential to moderate regional climate risks while illustrating trade-offs of solar intervention.
Conditions Necessary for Chlorine Activation in the Midlatitude Summer Lower Stratosphere
Authors: Laila V. Howar, Ross J. Salawitch, David M. Wilmouth, Eric J. Hintsa, Jennifer S. Hare, Thomas F. Hanisco, et al.
Synopsis: Using NASA ER-2 aircraft data from the 2021–2022 DCOTSS campaign, researchers examined whether chlorine activation in the North American Monsoon Anticyclone leads to ozone loss. Despite sampling cold, moist air conducive to activation, significant ClO enhancement was not observed due to low inorganic chlorine and limited ClONO₂ availability. However, simulations suggest that under increased stratospheric sulfate aerosol conditions, such as from volcanic eruptions or Solar Radiation Management interventions, chlorine activation and ozone depletion could become substantial.
Simulated Climate and Carbon Cycle Response to Arctic Ocean Albedo Modification
Authors: Jiu Jiang, Long Cao, Han Zhang
Synopsis: Using an Earth system model, researchers assessed Arctic Ocean Albedo Modification (AOAM), increasing seawater reflectivity to match sea ice, as a potential cooling strategy. By 2100, AOAM reduces Arctic warming by 1.6°C, delays 4°C warming by over 20 years, and prevents 16% sea ice loss. It also limits permafrost thaw by 6% and curbs carbon release by 22 PgC, though ocean carbon storage drops slightly. However, abrupt termination causes rapid climate shifts, highlighting both AOAM’s promise and its risks.
Tracing stratospheric transport using subannual plutonium-239 fallout in polar ice cores
Authors: Jinhwa Shin, Seungmi Lee, Yeongcheol Han, Heejin Hwang et al.
Synopsis: Ice core records from Greenland and Antarctica reveal the first subannual plutonium-239 (²³⁹Pu) deposition data (1940–1980 CE), offering new insight into stratospheric transport. Differences in fallout between the 1952 Ivy Mike and 1954 Operation Castle tests highlight how circulation patterns affect deposition timing. Seasonal fallout peaks in Antarctic summers indicate stronger stratosphere–troposphere exchange. These findings improve models of aerosol dispersion, volcanic impacts, and potential geoengineering effects.
Stratospheric aerosol forcing for CMIP7 (part 1): Optical properties for pre-industrial, historical, and scenario simulations (version 2.2.1) - Preprint
Authors: Thomas Jacques Aubry, Matthew Toohey, Sujan Khanal, Man Mei Chim, Magali Verkerk, et al.
Synopsis: A new CMIP7 stratospheric aerosol dataset (1750–2023) improves volcanic aerosol forcing estimates used in global climate models. Unlike CMIP6, it relies on volcanic sulfur emission data instead of limited pyrheliometer records, capturing small-to-moderate eruptions more accurately. CMIP7 shows a 29% higher mean stratospheric aerosol optical depth (SAOD) than CMIP6, influencing simulated surface temperatures by up to 0.07 °C. The study calls for annual dataset updates and further uncertainty evaluation.
Cirrus Cloud Thinning Simulations Constrained by Satellite Observations - Preprint
Authors: Ehsan Erfani
Synopsis: Cirrus cloud formation involves complex microphysics that challenge accurate modeling and affect predictions of aerosol impacts and cirrus cloud thinning (CCT) potential. By integrating satellite data with numerical and radiative transfer models, researchers identified two distinct formation pathways with differing radiative effects. These findings enhance understanding of aerosol–cloud interactions and provide fresh insights into CCT’s role in Earth’s radiation balance.
Solar Radiation Modification is projected to increase land carbon storage and to protect the Amazon rainforest - Preprint
Authors: Isobel M. Parry, Paul D. L. Ritchie, Olivier Boucher, Peter M. Cox, James M. Haywood, et al.
Synopsis: Using five Earth System Models, researchers evaluated Stratospheric Aerosol Injection. When SAI is used to lower global temperatures from SSP585 to SSP245 levels, global net primary productivity increases by 15.6% and land carbon storage by 5.9%, mainly due to CO₂ fertilization. Notably, Amazonian carbon storage rises by over 8%, suggesting that SAI could help protect the rainforest from climate-driven carbon losses despite reduced sunlight.
Rockets, Satellites, and Stratospheric Aerosol Injection: Regulating Human Impacts on Stratospheric Aerosols Under the Ozone Regime - Column
Authors: Daniel Bodansky & Nicolás E. Esguerra
Synopsis: The article warns that rising human activities, like rocket launches, space debris, and potential SAI, pose new risks to the ozone layer by altering stratospheric aerosol levels. It argues that the existing ozone regime under the Vienna Convention and Montreal Protocol is best suited to assess and, if needed, regulate these impacts. The authors propose a science-based, precautionary approach, including possible legal action to manage aerosol-related threats.
Healthy Climate Initiative - The Cooling Chronicle | Global Warming Could Reach 3°C by 2050
DSG - Confronting Climate Realities and Deliberating SRM at Climate Week NYC
CNN Health - It’s a bird! It’s a plane! It’s a chemtrail? A new conspiracy theory finds traction at Kennedy’s HHS
Euractiv - Can solar radiation management quicken global climate efforts?
Technosphere Earth - Climate tipping points should not be used to justify geoengineering
Yahoo News - MTG names her one positive to come from the shutdown: the end to ‘taxpayer-funded weather modification’ that isn’t really happening
Chris Martz - Contrails or Chemtrails? An Explainer for Dummies
French Academy of Sciences - Climate geoengineering: call for caution and rigorous supervision
Synopsis: The French Academy of Sciences emphasizes that the top priority must remain deep GHG reductions and adaptation to climate impacts. It issues three key recommendations on SRM: (1) establish an international ban on any SRM deployment; (2) support research on climate and atmospheric processes to rigorously assess SRM’s risks and potential; and (3) expand ethical and risk-related research while rejecting any climate experimentation. The Academy concludes that SRM lacks legitimacy as an intervention option.
Engagement Coordinator at Centre for Climate Repair | UK | Deadline: 05 November 2025
“Centre for Climate Repair is collaborating with scientists around the globe to investigate ways of removing greenhouse gases and cooling the planet, building a suite of knowledge for informed decision-making. Paired with rapid emissions reduction, we hope to be able to protect our planet and our future.”
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Discover Climate Repair: another kind of climate action | Centre for Climate Repair
“Discover Climate Repair: another kind of climate action. In the first seminar of the series, Prof Hugh Hunt introduces climate repair - actions that go beyond emissions reduction to consider the removal of GHGs and increasing the planet’s ability to reflect sunlight (you might have seen that in the news as “geoengineering” or “climate cooling”). Clara Botto, Director of Outreach at the Alliance for the Just Deliberation of Solar Geoengineering (DSG) will then delve into the controversies and considerations of adding another kind of climate action to global strategies.”
Climate Change Is Stupidly EASY To Stop — Andrew Song, Cofounder of Make Sunsets | Doom Debates
“My guest Andrew Song runs Make Sunsets, which launches weather balloons filled with sulfur dioxide (SO₂) into the stratosphere to reflect sunlight and cool the planet.”
Community Discussion of Cynthia Sharf podcast and near-term cooling governance | Healthy Planet Action Coalition
“Cynthia Scharf is Senior Fellow - Climate Interventions at the Centre for Future Generations, steering our work on climate intervention technologies and briefing senior climate officials in the EU and globally on the need to develop international guardrails and guidelines for solar geoengineering.”
Compton Lecture Series: Climate as a 4D Problem (Featuring David Keith) | UChicago Climate Systems Engineering initiative
“David Keith introduces the series, outlining the four dimensions of climate action: decarbonization, carbon removal, sunlight reflection, and adaptation; the four tools that can weaken the causal chain that stretches from economic activity to the impacts of climate change on humans and nature.”
Session on “Solar Geoengineering: The Case for an International Non-Use Agreement” @NYC Climate Week | Solar Geoengineering Non-Use Agreement
“There are growing scientific and political calls for an International Non-Use Agreement on Solar Geoengineering. This session brought together government representatives and academics to discuss why such a non-use agreement is urgently needed and to reflect on recent policy, legal, and scientific developments.”
SRM & Climate Justice | Chesapeake Climate Action Network
Earth Observations in the Era of Climate Overshoot: Novel Earth System Responses with Ben Poulter | International Space Science Institute
“Rising greenhouse-gas emissions from human activities are causing rapid changes to Earth’s climate. Despite efforts to mitigate emissions to limit warming below 1.5 degrees Celsius, changes in temperature appear to be heading for a temporary overshoot with unknown temperature peak and duration, and impacts to the Earth system. Climate overshoot, i.e., temporarily exceeding a temperature limit, is a relatively new concept, and the associated impacts, mitigation and adaptation needs are an active area of research.
Current space-based observing systems to monitor the land, ocean, cryosphere and atmosphere were designed during a phase of relatively stationary climate conditions or with the assumption that climate policies will stabilize temperatures in a fairly linear way. The characteristics of climate overshoot require rethinking and reevaluating satellite mission requirements related to temporal revisit, spatial resolution, spectral range, signal to noise, and overpass time. For example, abrupt permafrost thaw in high-latitudes, greenhouse-gas emissions from warming tropical wetlands, rapid glacier melt, ocean heatwaves and impacts on biogeochemistry, have unique signatures that current observing constellations will need to track for impacts, reversibility and stability. Additionally, an increasing number of climate intervention efforts to avoid or minimize climate overshoot, linked to carbon dioxide removal, methane removal, and solar radiation management, have their own set of specific monitoring requirements. Advances in technology, new partnerships between public, private and commercial organizations, and an expansion of computing power and algorithms have potential to keep pace with expanding observing requirements.”
Andreas Malm’s Public Lecture - Return of Repressed Heat: Towards a Freudo-Marxist Theory of Geoengineering | Bao Nguyen - Grad. Admin Comparative Literature
“As temperatures and emissions continue to soar in tandem, solar geoengineering is rising steadily on the agenda. Planes have already been launched to test the basics of sulphate aerosol injection. Denial of the climate crisis – a denial that comes in the most multifarious forms – appears to be poised for an upgrading into repression. This talk will argue that geoengineering would constitute a materialised repression of global warming, with all the dangers posed by a seemingly inevitable return of the repressed. Drawing on one interpretation of the passage from denial to repression, it will make a broader case for Freudo-Marxist theory as key to understanding contemporary climate politics. As we move deeper into the heat, the responses – including the material make-up of technologies for managing the fallout – have to be recognised in their constitutive psychic dimensions. Freudo-Marxist theory, in the tradition of the second generation of political Freudians and the Frankfurt school, is an indispensable guide to this age of catastrophe.”
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
Saturdays 25 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)
28 October | Online - Live Discussion: Could Solar Geoengineering Help or Harm the Amazon? by SRM360
31 October | Online - Introducing: Sunshade Temperature mitigation using Asteroids and Rings system by Planetary Sunshade Foundation
31 October | Online - Climate Intervention Virtual Symposia #21 (NEW)
3-7 November | Pune, India - 11th WMO Scientific Conference on Weather Modification
14 November | Online - Planetary Sunshade Foundation - annual update by Planetary Sunshade Foundation
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
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