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RESEARCH PAPER: Using optimization tools to explore stratospheric aerosol injection strategies (EGU)
RESEARCH PAPER: Conspiracy theories as engines of connection for enriched public debates on emerging technologies (Communications Earth & Environment)
WORKSHOP REPORT: The Governance of Arctic Climate Interventions (Harvard Kennedy School)
JOB OPPORTUNITY: Research Fellow in Climate Intervention (University of Birmingham)
UPCOMING EVENT: Confessions of a Climate Activist: Clean Energy Alone Can No Longer Save Us. We Need to Study Sunlight Reflection (MEER)
PODCAST: SAI can weaken CO2 greenhouse effect - Soden (Reviewer 2 does Geoengineering)
VIDEO: Can Geoengineering Save Us—Or Cook the Planet? (The Dispatch)
Read on to unpack more updates:
Effects of Warming and Stratospheric Aerosol Injection on Tropical Cyclone Distribution and Frequency: Results from a High-Resolution Global Circulation Model
Authors: Andrew Feder, David Allan Randall, and Donald Dazlich
Synopsis: This study uses a high-resolution (30 km) GCM to examine how SAI affects tropical cyclones (TCs). Three 10-year simulations were run: a recent-past calibration, SSP5-8.5 late-century warming, and SSP5-8.5 with SAI limiting warming to 1.5 K. A new TC-tracking algorithm reveals that while SAI restores global storm counts to late-20th-century levels, basin-scale changes in storm number and intensity persist, strongly influenced by ENSO shifts under both warming and intervention.
Building a comprehensive library of observed Lagrangian trajectories for testing modeled cloud evolution, aerosol–cloud interactions, and marine cloud brightening
Authors: Ehsan Erfani, Robert Wood, Peter Blossey, Sarah J. Doherty, and Ryan Eastman
Synopsis: Researchers built a library of 2200 trajectories from NE Pacific stratocumulus clouds (2018–2021) using eight cloud-controlling factors and PCA, reducing variability to two components. From these, 54 cases capture diverse conditions for LES studies of marine cloud brightening. Simulations show aerosols can delay breakup and boost radiative effect, but responses hinge on precipitation–aerosol feedback: precipitating cases drive rapid breakup, while non-precipitating cases follow deepening–warming dynamics.
Conspiracy theories as engines of connection for enriched public debates on emerging technologies
Authors: Gabriel Dorthe
Synopsis: This paper examines how conspiracy theories around COVID-19 mRNA vaccines and solar geoengineering (“chemtrails”) reinforce one another, complicating science communication and policy. Based on ethnographic fieldwork in the US and Europe since 2015, including social media analysis, gatherings, and interviews, the study highlights mutual distrust between science policy and conspiratorial thinking. It argues that the blending of disparate claims reveals how publics connect science, politics, and fears, offering insights for communicating on vaccines and climate interventions.
Using optimization tools to explore stratospheric aerosol injection strategies
Authors: Ezra Brody, Yan Zhang, Douglas G. MacMartin, Daniele Visioni, Ben Kravitz, and Ewa M. Bednarz
Synopsis: This study evaluates optimization strategies for SAI, focusing on how injection latitude and distribution affect climate outcomes. Using climate model simulations at seven latitudes, the authors validate linearity and apply optimization tools to explore trade-offs. Results show that while no strategy fully offsets greenhouse gas–driven changes, optimized multi-latitude approaches can better balance regional temperature and precipitation at ~1 °C cooling. However, improvements may be marginal at lower cooling levels, highlighting both potential and limits of strategic SAI deployment.
Absorption effect on light scattering by dust particles in physical optics approximation
Authors: K. S. Salnikov, N. V. Kustova, D. N. Timofeev, I. V. Tkachev & A. V. Konoshonkin
Synopsis: This study analyzes light scattering by irregular cosmic dust particles (5–100 μm) using the physical optics approximation, focusing on conditions where backscattering reduces to specular reflection. Measurements on pyroxene glass (n = 1.6847 + i0.0373) and graphite (n = 1.48 + i0.003) show size-dependent behavior: weakly absorbing graphite requires >100 μm particles for purely specular backscatter, while strongly absorbing pyroxene achieves it at ~5 μm. Findings aid stratospheric aerosol injection modeling and lidar interpretation.
Photophoretic flight of perforated structures in near-space conditions
Authors: Benjamin C. Schafer, Jong-hyoung Kim, Felix Sharipov, Gyeong-Seok Hwang, et al.
Synopsis: Lightweight nanofabricated structures can be lofted into near-space via photophoretic forces, especially through thermal transpiration. Using a hybrid model, researchers optimized membrane spacing, perforation density, and ligament distribution to balance strength and lift. Experiments showed levitation of 1-cm devices at 26.7 Pa under half-sunlight intensity. A 3-cm prototype could carry 10 mg at 75 km altitude, enabling climate sensing, communications, and Mars exploration.
Future hydro-climatic changes associated with global warming and stratospheric aerosol intervention scenarios across Central-South Asia and the Tibetan Plateau - Preprint
Authors: Azfar Hussain, Abolfazl Rezaei, Ping Zhu, Guanglang Xu, Chao Yang, Yan Ma, et al.
Synopsis: This study examines hydroclimatic changes in the Central and South Asian Tibetan Plateau (CSATP) under future high-emissions (SSP5-8.5) and Geo-SAI scenarios using CESM2-WACCM simulations. High GHG emissions intensify temperature, precipitation, runoff, and vegetation growth, with stronger seasonality and earlier runoff peaks, especially in South Asia and eastern central Asia. Geo-SAI reduces warming and dampens extremes in water storage and runoff but increases soil moisture and vegetation variability, showing regionally uneven impacts. Findings suggest SAI could mitigate GHG-driven hydroclimatic extremes in CSATP while introducing trade-offs.
A schematic plot of the linear model of climate responses to GHG and SAI forcings
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ScienceDirect - AGU Posts Principles to Guide—and Foster—Geoengineering Research
SRM360 - African Ministers Reject SRM – an “Unacceptable Climate Solution”
Climate Cosmos - Geoengineering: A Risky but Necessary Solution to Climate Change?
Operaatio Arktis - How to work towards a more responsible approach to preventing climate risks and promoting research on climate interventions
Harvard Kennedy School - Workshop Report: The Governance of Arctic Climate Interventions
Research Fellow in Climate Intervention at University of Birmingham | Birmingham | Deadline' 5th October 2025
"‘Quantifying efficacy and risks of solar radiation management approaches using natural analogues’ (QUESTION) aims to study SRM using natural analogues, such as wildfires and volcanic eruptions. These analogues have happened in the recent Earth history and therefore no worrying of side-effects from any new field experiments, and will give us clues what might happen should we attempt to do solar radiation management.
In QUESTION, the University of Birmingham and University of Edinburgh, and the Center for International Climate Research (CICERO, Norway) will work together to will address challenges in separating SRM signals from other factors, improving climate models, and attributing climate responses of SRM."
Fully Funded PhD Project: Geoengineering impacts on large-scale utilization of renewable energies and on global justice of renewable development at University of Birmingham
"This project will address the critical challenge of geoengineering impacts on renewable energies and global justice, particularly concerning Solar Radiation Management (SRM). It aims to quantify the impacts of SRM approaches on the balance between renewables and energy demand. The research will provide novel insights into climate justice from an SRM and energy perspective, supporting green energy policymaking with real-world influential impacts."
26 August | Online - Making sense of wildfires and solar geoengineering by SRM360
27 August | Vienna - Do we need to darken the sun? by TU Wien (NEW)
30 August | Online - Climate Intervention Research and Role of Civil society by Healthy Climate Initiative (NEW)
04-05 September | Washington DC - 2025 RFF and Harvard SRM Social Science Research Workshop: Governance in a Fractured World
07 September | Online - Confessions of a Climate Activist: Clean Energy Alone Can No Longer Save Us. We Need to Study Sunlight Reflection by MEER (NEW)
30 September | Belgium - Grappling with accelerating climate risks - Is it time to explore research into Solar Radiation Modification? by Euractive
6 – 9 October | Online - Virtual workshop series on Stratospheric Aerosol Injection
17 October - Introducing SkyScroll by Planetary Sunshade Foundation
23 October | Helsinki - ATLAS25: Risk Management of Earth System Tipping Points by Operaatio Arktis
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
SAI can weaken CO2 greenhouse effect - Soden | Reviewer 2 does Geoengineering
"Brian Soden discusses his recent study on injecting absorptive aerosols, such as black carbon, into the upper stratosphere to weaken the CO₂ greenhouse effect.
The conversation addresses the radiative physics underpinning this concept, its potential cooling efficiency relative to conventional scattering aerosols, and associated environmental risks. While model results indicate the method could theoretically be effective, Soden remains sceptical about its practical viability.
Paper: He, H., Soden, B. J., Vecchi, G. A., & Yang, W. (2025). Stratospheric aerosol injection can weaken the carbon dioxide greenhouse effect. Communications earth & environment, 6(1), 485. https://doi.org/10.1038/s43247-025-02466-z"
Too Hot to Handle?: Facing a Future Beyond 1.5°C | Outrage + Optimism: The Climate Podcast
"This week, Tom, Christiana and Paul grapple with the latest science, the looming risks of climate tipping points, and the urgent need to prepare for the worst - even while hoping and working for the best. They’re joined by Ricken Patel, former Founding CEO of global activism nonprofit Avaaz, who is now calling us to take the possibility of overshoot seriously, and to build the political, technological and social capacity to bring temperatures back down.
From nature-based solutions to novel carbon dioxide removal and solar radiation management, this episode considers the broad spectrum of options on the table, and the challenges they present. Why has climate contingency planning been missing from the political debate? And does simply talking about it risk slowing climate action?"
Global Views on Geoengineering | To Save The World
"Chad Baum is a professor in Denmark who has, with his colleagues, conducted a massive global public opinion survey about attitudes toward geoengineering."
Can Geoengineering Save Us—Or Cook the Planet? | The Dispatch
"Dr. David Keith, professor of geophysical sciences at the University of Chicago and founder of Carbon Engineering, joins Jonah Goldberg to explain the controversy surrounding geoengineering. Together, he and Jonah brainstorm ways to decarbonize the economy, argue over the fine print of climate policy, and wonder if humanity can fix the planet without accidentally turning it into a giant Easy-Bake Oven."
Is it time to talk about Solar Radiation Management? | Tito - AirMiners
Facing Big Questions on Climate & Economics | Climate Emergency Forum
"This session captures a powerful and often sobering discussion featuring economist Steve Keen, scientist Ye Tao, and moderator Herb Simmens, recorded during a MEER (Mirror Earth Energy Rebalancing) event.
The dialogue ranges widely—from the shortcomings of the IPCC’s economic assessments and reluctance to consider geoengineering, to strategies for equitable climate action such as redistributing consumption burdens from the poor to the ultra‑rich. Audience members raise provocative ideas, from revolution to nature‑based solutions, and Keen responds with both caution and urgency. Ye underscores that even the global “median” lifestyle is unsustainable, advocating for technical innovations like reflective materials in agriculture to boost yields while lowering heat stress, alongside building community resilience."
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