SOLAR GEOENGINEERING WEEKLY SUMMARY (09 DECEMBER - 15 DECEMBER 2024) Subscribe to our newsletter to receive monthly updates on Solar Geoengineering: Solar Geoengineering Updates <https://solargeoengineeringupdates.substack.com?utm_source=substack&utm_campaign=publication_embed&utm_medium=email> Monthly news summaries about solar geoengineering. Links to scientific papers, news articles, jobs, podcasts, and videos. <https://solargeoengineeringupdates.substack.com?utm_source=substack&utm_campaign=publication_embed&utm_medium=email> By Andrew Lockley <https://solargeoengineeringupdates.substack.com?utm_source=substack&utm_campaign=publication_embed&utm_medium=email> ------------------------------ RESEARCH PAPERSClimate intervention research in the World Climate Research Programme: a perspective <https://www.frontiersin.org/journals/climate/articles/10.3389/fclim.2024.1505860/full>
Hurrell, J. W., Haywood, J. M., Lawrence, P. J., Lennard, C. J., & Oschlies, A. (2024). Climate intervention research in the World Climate Research Programme: a perspective. *Frontiers in Climate*, *6*, 1505860. *Abstract* The 2023 World Climate Research Programme (WCRP) Open Science Conference underscored the critical need for increased climate change mitigation and adaptation efforts, along with enhanced climate knowledge and decision-making systems. This Perspective discusses climate intervention (CI) within WCRP’s research framework, emphasizing three main approaches: terrestrial carbon dioxide removal (CDR), marine CDR, and solar radiation modification (SRM). As global anthropogenic greenhouse gas emissions continue to rise, CI strategies are increasingly recognized as potentially critical supplements to traditional mitigation methods. We call for WCRP to take a leadership role in CI research, highlighting the need for inclusivity and collaboration, especially with researchers from the Global South, to establish a firm scientific foundation for an equitable and comprehensive assessment of the benefits and risks of CI approaches relative to the risks of anthropogenic climate change. Impact of clouds on vegetation albedo quantified by coupling an atmosphere and a vegetation radiative transfer model <https://egusphere.copernicus.org/preprints/2024/egusphere-2024-3614/> Wolf, K., Jäkel, E., Ehrlich, A., Schäfer, M., Feilhauer, H., Huth, A., ... & Wendisch, M. (2024). Impact of clouds on vegetation albedo quantified by coupling an atmosphere and a vegetation radiative transfer model. *EGUsphere*, *2024*, 1-30. *Abstract* This paper investigates the influence of clouds on vegetation albedo. For this purpose, we use coupled atmosphere-vegetation radiative transfer (RT) simulations combining the library for Radiative transfer (libRadtran) and the vegetation Soil Canopy Observation of Photosynthesis and Energy fluxes (SCOPE2.0) model. Both models are iteratively linked to more realistically simulate cloud–vegetation-radiation interactions above three types of canopies represented by the spherical, erectophile, and planophile leaf angle distributions. The coupled models are applied to simulate solar, spectral and broadband irradiances under cloud-free and cloudy conditions, with the focus on the visible to near-infrared wavelength range from 0.4 to 2.4 µm wavelengths. The simulated irradiances are used to investigate the spectral and broadband effect of clouds on the vegetation albedo. It is found that changes in solar zenith angle and cloud optical thickness are equally important for variations in the vegetation albedo. For solar zenith angles less than 50° –60°, the vegetation albedo is increased by clouds by up to 0.1. The greatest increase in albedo was observed during the transition from cloud-free to cloud conditions with a cloud optical thickness (τ ) of about 6. For larger values of τ the vegetation albedo saturates and increases only slightly. The increase of the vegetation albedo is a result of three effects: (i) dependence of the canopy reflectivity on the direct and diffuse fraction of downward irradiance, (ii) the shift in the spectral weighting of downward irradiance due to scattering and absorption by clouds, and (iii) multiple scattering between the top of canopy and the cloud base. The observed change in vegetation albedo due to cloudiness is parameterized by a polynomial function, representing a potential method to include cloud–vegetation-radiation interactions in numerical weather prediction and global climate models. Assessing GFDL-ESM4.1 Climate Responses to a Stratospheric Aerosol Injection Strategy Intended to Avoid Overshoot 2.0°C Warming <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2024GL113532> Zhang, S., Naik, V., Paynter, D., Tilmes, S., & John, J. (2024). Assessing GFDL‐ESM4. 1 climate responses to a stratospheric aerosol injection strategy intended to avoid overshoot 2.0 C warming. *Geophysical Research Letters*, *51*(23), e2024GL113532. *Abstract* In this work, we apply the GFDL Earth System Model (GFDL-ESM4.1) to explore the climate responses to a stratospheric aerosol injection (SAI) scenario that aims to restrict global warming to 2.0°C above pre-industrial levels (1850–1900) under the CMIP6 overshoot scenario (SSP5-34-OS). Simulations of this SAI scenario with the CESM Whole Atmosphere Community Climate Model (CESM2-WACCM6) showed nearly unchanged interhemispheric and pole-to-Equator surface temperature gradients relative to present-day conditions around 2020, and reduced global impacts, such as heatwaves, sea ice melting, and shifting precipitation patterns (Tilmes et al., 2020, https://doi.org/10.5194/esd-11-579-2020). However, model structural uncertainties can lead to varying climate projections under the same forcing. Implementing identical stratospheric aerosol radiative properties in GFDL-ESM4.1, which has a much lower Effective Climate Sensitivity compared to CESM2-WACCM6, resulted in a decrease in global-mean surface temperature by more than 1.5°C and a corresponding reduction in precipitation responses. Two major reasons contribute to the different temperature response between the two models: first, GFDL-ESM4.1 has less warming in the SSP534-OS scenario; second, GFDL-ESM4.1 has shown more pronounced cooling in response to the same stratospheric AOD perturbation. Notably, the Southern Hemisphere experiences substantial cooling compared to the Northern Hemisphere, accompanied by a northward shift of the Intertropical Convergence Zone (ITCZ). Furthermore, our analysis reveals that spatially heterogeneous forcing within the SAI scenario results in diverse climate feedback parameters in the GFDL-ESM4.1 model, through varying surface warming/cooling patterns. This research highlights the importance of considering model structural uncertainties and forcing spatial patterns for a comprehensive evaluation of future scenarios and geoengineering strategies. The strategic and governance implications of solar radiation management: perspectives from delegates of international climate negotiations <https://par.nsf.gov/biblio/10559663> Cherry, T., Kallbekken, S., McEvoy, D., & Siu, W. (2024). The strategic and governance implications of solar radiation management: perspectives from delegates of international climate negotiations. *Environmental Research Letters*. *Abstract* The lack of progress in addressing climate change has led to increased interest in solar radiation modification (SRM)—a collection of large-scale interventions that cool the planet by managing the amount of solar radiation that reaches the earth. SRM complicates climate change governance because, in addition to advancing collective action to reduce greenhouse gas emissions, governance needs to restrain unilateral SRM action while balancing diverging actor interests, ethical risks and scientific uncertainty. We survey international climate policy experts for their assessments of the potential for effective global governance of SRM and the likelihood of possible international responses to unilateral SRM scenarios. Experts are pessimistic about the global community achieving effective SRM governance, and they believe unilateral SRM action will trigger international responses and conflicts. Experts believe softer responses are most likely (e.g., diplomatic sanctions) but the potential for stronger responses, including military action, are non-trivial. Relative to the Global North, experts from the Global South are relatively more supportive of SRM, including the development of SRM, the inclusion of SRM in international negotiations, and the deployment of SRM in a climate emergency. Climate sensitivity and feedback trends using energy consumption rates: Runaway feedback passes a key threshold likely requiring solar geoengineering <https://www.researchgate.net/publication/383918692_Climate_sensitivity_from_feedback_trends_using_energy_consumption_rates_Runaway_feedback_threshold_passed_requiring_solar_geoengineering> Feinberg, A. Climate sensitivity and feedback trends using energy consumption rates: Runaway feedback passes a key threshold likely requiring solar geoengineering. *Abstract* This paper provides climate sensitivity estimates and feedback trend analysis using data from 1975-2024 including projections and approximations for earlier periods. Modeling is accomplished by focusing on normalized correlated rates (NCRs) finding: 0.0204/year to 0.029/year for global warming (GW) increases, 0.0209/year for CO2 increases, 0.0124/year for energy consumption (EC) rate increases, and 0.0107/year for population increases. These NCR point estimates indicate that global warming is increasing by a factor of 1.65 to 1.83 times faster than energy consumption, assessed as the leading NCR indicator, from 1975 to 2021. The reason with respect to this GW to energy consumption ratio is due to feedback amplification. This is supported by the fact that this study finds the normalized correlated rates for forcing and energy consumption show approximate equivalency in the period studied. The projected 2020-2024 feedback amplification estimates using the EC approach are 2.0 to 2.07, respectively. A feedback amplification of 2.0 (approximately equal to -2.83Wm-2K-1) doubles the forcing indicating that in 2024, more than half of global warming is likely due to feedback. This runaway threshold value in this study is denoted as a feedback-halfway (FH) tipping point, where if forcing were removed, one would question if global warming could be completely resolved without additional reverse forcing. Therefore study recommends minimally annual solar geoengineering mitigating methods to be included in the Paris Accord as an aid to help reduce climate risks. The study also estimates that 75% to 90.5% of this feedback problem is due to water vapor which has had a very large concerning increase from 2022 to 2024. Furthermore, EC approach additionally finds that feedback amplification has jumped from 0.0136 yr-1 to 0.0161 yr-1 from 2022 to 2024. Depending on the average rate, trends analysis indicates that by 2047, the earliest we may reach 10 billion people, feedback amplification could reach a value of 2.4 to 5.1. Furthermore, by 2082, the year estimated for 2xCO2, at the modeled likely rates, feedback amplification is projected to be in a range from 2.9 to 5.7 which equates to -1.53Wm-1K-1 to -0.81 Wm-1K-1, respectfully. This yields an ECS range from 2.4K to 4.6K in agreement with the reported estimated range in AR6. This paper also overviews recent data showing an urbanization forcing influence indicating that the CO2 forcing attribution may be lower by 10.7% if this forcing is considered. Since the rate of EC is shown to be a main driver for the forcing rate, we note that 75% of energy is consumed in urban areas and NCR assessment indicates energy consumption has exceeded the population growth rate by a factor of 1.159 or about 16% higher. Results also show that under “zero population growth”, the assessment indicates that global warming increases would likely be reduced by about half. ------------------------------ WEB POSTSEU should ban space mirrors and other solar geoengineering, scientists say <https://www.theguardian.com/environment/2024/dec/09/eu-should-ban-space-mirrors-and-other-solar-geoengineering-warn-scientists>(The Guardian)Will Scientists Know if SRM Caused Extreme Weather? <https://srm360.org/article/will-scientists-know-if-srm-caused-extreme-weather/> (SRM360)The risks of ignoring SRM in the shadow of a second Trump Administration <https://sgdeliberation.org/the-risks-of-ignoring-srm-in-the-shadow-of-a-second-trump-administration/> (DSG)Governance Recommendations for the For-profit SAI Startup “Stardust” <https://srm360.org/perspective/governance-recommendations-for-stardust/> (SRM360)Unilateral Deployment: Could a Single Country Change the Global Climate? <https://srm360.org/article/unilateral-deployment-could-a-country-change-the-global-climate/> (SRM360)UN Agreements On Oceanic Geoengineering Don’t Cover Dominant Land-Based Systems <https://cleantechnica.com/2024/12/11/un-agreements-on-oceanic-geoengineering-dont-cover-dominant-land-based-systems/> (Clean Technica) ------------------------------ REPORTSScoping Note on Applicable Legal Frameworks <https://co-create-project.eu/publication/scoping-note-on-applicable-legal-frameworks/> (Co-Create)Near-term Climate Risk and Intervention: A Roadmap for Research and Decision-making <https://www.silverlining.ngo/near-term-climate-risk-and-intervention> (SilverLining) ------------------------------ JOB OPPORTUNITIESGeoengineering Law and Policy Project Director at Emmett Institute on Climate Change and the Environment, UCLA School of Law | Deadline: 15 February 2025 <https://recruit.apo.ucla.edu/JPF10063> "The Project Director will develop and oversee a portfolio of high-impact project activities to advance understanding and practice related to the law and policy of geoengineering (active technological interventions to manage climate change and its impacts); develop and manage partnerships with a diverse international group of collaborators; supervise project research staff and contractors; collaborate with Emmett Institute and Law School staff on project-related administrative matters; and raise external resources to support the ongoing activities and expansion of the project. The Project Director will dually report to the Emmett Institute faculty director and deputy director, and will work at the direction of, and in collaboration with, the Emmett Institute executive director, deputy director, and faculty directors and co-directors. Depending on their interests and other commitments, the Project Director may develop opportunities for UCLA students related to the law and policy of geoengineering." Staff Scientist <https://www.degrees.ngo/careers/staff-scientist/> (Deadline to apply: 09 January 2025), Programmes Director <https://www.degrees.ngo/careers/job-opportunity-programmes-director/>(Deadline: 02 January 2025), Operations Officer <https://www.degrees.ngo/careers/job-opportunity-operations-officer/> (Deadline: 02 January 2025)at The Degrees Initiative | UK-Remote "The Degrees Initiative is a UK-based NGO that builds the capacity of developing countries to evaluate solar radiation modification (SRM), a controversial proposal for reducing some impacts of climate change by reflecting sunlight away from the Earth. Degrees is neutral on whether SRM should ever be used, but we believe that developing countries should be empowered to conduct their own research and to play a central role in SRM discussions. The initiative has been working in different forms for over a decade and our work receives worldwide coverage and widespread acclaim." ------------------------------ *UPCOMING EVENTS*(NEW) Solar radiation modification: What should Europe’s strategy be? by Scientific Advice Mechanism to the European Commission <https://us02web.zoom.us/webinar/register/WN_zMVEie0PThCasf0lFO_FSw#/registration> | 23 January 2025 | Online(NEW) Solar Radiation Modification: What’s at stake for society? by Scientific Advice Mechanism to the European Commission <https://us02web.zoom.us/webinar/register/WN_Sra0pIz1Q7KeHjzxHOaMFQ#/registration> | 03 February 2025 | Online*2025 Solar Radiation Management Annual Meeting by Simons Foundation <https://www.simonsfoundation.org/event/solar-radiation-management-annual-meeting-2025/> | 24-25 April 2025 | New York**The 2025 Degrees Global Forum <https://substack.com/redirect/8521c00b-652a-4d78-822f-7ae393c57068?j=eyJ1IjoiMjJrMHl3In0.wQQsFypG52typ8FI2nhnJ8eUoUIIkdCkuhmzxNYKtgE> | 12-16 May 2025 | Cape Town, South Africa**Artic Repair Conference 2025 by University of Cambridge & Center for Climate Repair <https://substack.com/redirect/90f81f14-d09c-4418-8d97-c6621d753433?j=eyJ1IjoiMjJrMHl3In0.wQQsFypG52typ8FI2nhnJ8eUoUIIkdCkuhmzxNYKtgE> | 26-28 June 2025 | Cambridge UK* Solar Geoengineering Events Calendar <https://teamup.com/ks64mmvtit583eitxx> ------------------------------ PODCASTSAndean glaciers & SRM - Fernandez | Reviewer 2 does geoengineering Andean glaciers & SRM - Fernandez Reviewer 2 does geoengineering 1:00:19 <https://podcasts.apple.com/us/podcast/andean-glaciers-srm-fernandez/id1529459393?i=1000680097266&uo=4> "Is it too late for SRM to save South American glaciers? Alfonso Fernandez discusses his paper on the impact of SRM on the glaciers of the Andes. Fernández, A., Manquehual-Cheuque, F. & Somos-Valenzuela, M. Impact of Solar Radiation Management on Andean glacier-wide surface mass balance. npj Clim Atmos Sci 7, 257 (2024). https://doi.org/10.1038/s41612-024-00807-x"; ------------------------------ YOUTUBE VIDEOSBeyond Emissions Reduction | Climate Emergency Forum <https://www.youtube.com/watch?v=KeVs-I7Xt5A> “The panel features experts like Dr. Shaun Fitzgerald, the Executive Director of the Center for Climate Repair at Cambridge University, and Jill Storey, Marine Carbon Dioxide Removal Advisor with the World Ocean Council. They explore innovative approaches to climate change that extend beyond traditional emissions reduction strategies, emphasizing the urgent need for greenhouse gas removal and adaptation measures to combat the escalating climate crisis. Dr. Fitzgerald highlights the importance of increasing knowledge in climate repair and the necessity of achieving net negative emissions to effectively address existing greenhouse gases in the atmosphere. He discusses the critical role of research in understanding the implications of solar radiation management and other geoengineering strategies. Jill Storey underscores the urgent requirement to remove 10 gigatons of carbon dioxide annually by 2050, advocating for ocean-based solutions that leverage the ocean's capacity to store carbon while also addressing the need for robust industry development in carbon removal. As the conversation unfolds, panelists like Dr. Leonardo Valenzuela Pérez from Ocean Visions and climate educator Paul Beckwith engage in a dynamic dialogue about the complexities of climate solutions and the importance of collaboration across sectors. The discussion emphasizes that while emissions reduction remains vital, immediate action on carbon removal is equally crucial to avert catastrophic climate impacts. This compelling exchange invites viewers to consider diverse perspectives and innovative strategies in the fight against climate change, highlighting the collaborative efforts needed to secure a sustainable future.” Climate Change Geoengineering and Risk | Waide Center for Applied Ethics | Fairfield University <https://www.youtube.com/watch?v=QPvwX2bGIF8>Being Frank & Honest About Climate Change with Climate Scientist Kevin Anderson | Climate Chat <https://www.youtube.com/watch?v=l8Q8RQ4fbcQ> “In our third interview with climate scientist Kevin Anderson, we will cover why climate scientists need to be more frank and honest about emissions scenarios, why the rich cutting their emissions is key to staying below 2ºC of warming, the need for solar geo-engineering, COP29, and other subjects. Kevin Anderson holds the Zennström professorship at Uppsala University and is chair of energy and climate change at the School of Mechanical, Aerospace and Civil Engineering (MACE) at the University of Manchester. He has been Deputy and Interim Director of the Tyndall Centre. He is a non-executive director of Greenstone Carbon Management. Kevin is research active with recent publications in Science, Nature and Nature Geosciences. Kevin engages widely across all tiers of government (UK and Sweden) on issues ranging from shale gas, aviation and shipping to the role of climate modelling (IAMs), carbon budgets and ‘negative emission technologies. His analysis previously contributed to the framing of the UK’s Climate Change Act and the development of national carbon budgets. Kevin has a decade’s industrial experience, principally in the petrochemical industry. He is a chartered engineer and a fellow of the Institution of Mechanical Engineers.” Marine Cloud Brightening | Cool The Country <https://www.youtube.com/watch?v=NRbLbcilayY> “Flettner Rotors are spinning vertical tubes that work rather like airplane wings: they can power a boat at twice the speed the wind is blowing. These rotors are just one element of Stephen Salter’s carefully engineered, remote-controlled, wind-powered boats designed to spray a fine mist of sea water. As that mist of water evaporates, it will create bright, reflective clouds. Operating off the coast of Western Australia in the summer, those boats could move back and forth quickly to wherever the clouds they create would be carried ashore on the prevailing breezes. The heat engine of that region is a danger when cloud cover is minimal and the sun beats down. Long-term, the benefits of water-harvesting and reforesting are many-fold and lasting, but Marine Cloud Brightening could buy us time while forests and wetlands grow. Australia could also be a testing ground for technology that the whole world may soon need. We are not doing enough to slow greenhouse gas emissions, and temperatures will continue to rise. Outside of our summer, boats built to cool the Australian heat engine could be hired out to India, creating clouds where they would best slow the melting of glaciers in the Himalayas. Or they could create clouds over the Indo-Pacific Warm Pool, the driver of ever-hotter summers across Asia.” Physical, biological and social risks associated with solar radiation management - Wolfgang Cramer | Pathways Initiative – Future Earth <https://www.youtube.com/watch?v=Pd_mJYj6dhk> “Wolfgang Cramer (CNRS, French National Committee for Future Earth) introduces the concept of geoengineering, with a particular focus on solar radiation management (SRM). He explains that while SRM has the potential to mitigate temperature rise, it does not address other critical climate issues and the unintended consequences of SRM could be devastating.” Scientists Warn Against Solar Geoengineering | Vantage with Palki Sharma | Firstpost <https://www.youtube.com/watch?v=ocomMgeO-iM> “Is solar geoengineering a climate-solution or a pandora's box? According to European Union scientists, it is the latter. They have issued a warning about solar geoengineering, urging the EU to ban space mirrors and other solar geoengineering methods. Solar geoengineering, which refers to blocking sun's rays, promises to offset climate change. But scientists are increasingly claiming that it is a dangerous gamble. So which one is it and why?” How SilverLining is Studying Rapid Responses to Climate Change | WebsEdge Science <https://www.youtube.com/watch?v=HYSEZoSZ-7U> “SilverLining is at the forefront of groundbreaking research aimed at understanding and mitigating climate change through innovative stratospheric studies. The stratosphere, a critical component of our climate system, is undergoing significant changes due to factors like space and air traffic, mega fires, and pollution. SilverLining collaborates with scientists to explore the potential of stratospheric aerosol interventions, inspired by natural experiments from volcanic eruptions that have demonstrated a cooling effect on the planet. By enhancing our understanding of aerosol distribution and its interaction with solar radiation, SilverLining seeks to develop effective strategies for climate cooling. Central to SilverLining's mission is the use of stratospheric balloons for comprehensive observation. These balloons, cost-effective and versatile, are pivotal in gathering data over extended periods and vast areas, offering insights into the evolving stratosphere. SilverLining is pioneering efforts to improve the retrieval of balloon payloads, ensuring valuable instruments are reused, thus optimizing research efficiency. Their work involves simulating and modeling aerosol behavior to predict and create environmentally friendly exhaust environments, crucial for understanding the full impact of aerosols on climate dynamics. The significance of SilverLining's research lies in its potential to inform global climate strategies, emphasizing transparency and accessibility. By investing in resources and knowledge-sharing, particularly in the Global South, SilverLining aims to empower communities most affected by climate change. Their work not only advances scientific understanding but also contributes to public safety and environmental welfare, highlighting the delicate balance required in stratospheric interventions to avoid disrupting global precipitation patterns. SilverLining's efforts are vital in safeguarding the health of the stratosphere and the ozone layer, ensuring a sustainable future for all." -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/geoengineering/CAHJsh98FnHLaWkDMMYLa5RbiQWaPwQ5c-xVyySR3_ixD%2BsyrTg%40mail.gmail.com.
