*Subscribe to the Solar Geoengineering Updates Newsletter here:* 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> WEEKLY SUMMARY (16 OCTOBER - 22 OCTOBER 2023) ------------------------------ RESEARCH PAPERSThe Ethics of Volcano Geoengineering <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023EF003714>
Cassidy, M., Sandberg, A., & Mani, L. (2023). The ethics of volcano geoengineering. *Earth's Future*, *11*(10), e2023EF003714.*Abstract:*Volcano geoengineering is the practice of altering the state of volcanic systems and/or volcanic eruptions to exploit them or mitigate their risk. Although many in the field insist there is little that can be done to mitigate the hazard, past examples of both intentional and inadvertent volcano interventions demonstrate that it is technically feasible to reach volcano plumbing systems or alter atmospheric processes following eruptions. Furthermore, we suggest that economical, political, and environmental pressures may make such interventions more common in the future. If volcano geoengineering ever becomes a discipline, it will need to overcome many safety and ethical concerns, including dealing with uncertainty, deciding on philosophical approaches such as a consequentialism or precautionary principle, justice and inequality, military uses, cultural values, and communication. We highlight that while volcano geoengineering has significant potential benefits, the risks and uncertainties are too great to justify its use in the short term. Despite this, because of the potential large benefits to society, we believe there is a strong ethical case to support research into the efficacy and safety of volcano geoengineering for its potential future use. We propose that rigorous governance and regulation of any volcano geoengineering is required to protect against potential risks, to enable potentially valuable and publicly available research (e.g., quantification of efficacy and safety), to ensure that any future policy must be co-created through community engagement, and that volcano geoengineering should only be considered as part of larger mitigation practices. Characterizing climate pathways using feature importance on echo state networks <https://arxiv.org/abs/2310.08495> Goode, K., Ries, D., & McClernon, K. (2023). Characterizing climate pathways using feature importance on echo state networks. *arXiv preprint arXiv:2310.08495*.*Abstract:*The 2022 National Defense Strategy of the United States listed climate change as a serious threat to national security. Climate intervention methods, such as stratospheric aerosol injection, have been proposed as mitigation strategies, but the downstream effects of such actions on a complex climate system are not well understood. The development of algorithmic techniques for quantifying relationships between source and impact variables related to a climate event (i.e., a climate pathway) would help inform policy decisions. Data-driven deep learning models have become powerful tools for modeling highly nonlinear relationships and may provide a route to characterize climate variable relationships. In this paper, we explore the use of an echo state network (ESN) for characterizing climate pathways. ESNs are a computationally efficient neural network variation designed for temporal data, and recent work proposes ESNs as a useful tool for forecasting spatio-temporal climate data. Like other neural networks, ESNs are non-interpretable black-box models, which poses a hurdle for understanding variable relationships. We address this issue by developing feature importance methods for ESNs in the context of spatio-temporal data to quantify variable relationships captured by the model. We conduct a simulation study to assess and compare the feature importance techniques, and we demonstrate the approach on reanalysis climate data. In the climate application, we select a time period that includes the 1991 volcanic eruption of Mount Pinatubo. This event was a significant stratospheric aerosol injection, which we use as a proxy for an artificial stratospheric aerosol injection. Using the proposed approach, we are able to characterize relationships between pathway variables associated with this event. Understanding the Urgent Need for Direct Climate Cooling <https://essopenarchive.org/users/673263/articles/672102-understanding-the-urgent-need-for-direct-climate-cooling> Clarke, W. S., Elsworth, C., Field, L. A., Hoffmann, A., MacCracken, M. C., Macdonald, J., ... & Tulip, R. (2023). Understanding the Urgent Need for Direct Climate Cooling. *Authorea Preprints*.*Abstract:*The intensifying impacts of climate change are exceeding projections and amplifying the risk of catastrophic harm to the environment and society throughout the 21st century. Planned and proposed rates of emissions reduction and removal are not proceeding at a pace or magnitude to meet either the 1.5°C or 2.0°C targets of the Paris Agreement. Moreover, the impacts, damage and loss occurring at today’s 1.2°C of global warming are already significantly disrupting the environment and society. Relying exclusively on greenhouse gas (GHG) emissions reduction and removal without including climate cooling options is thus proving incompatible with responsible planetary stewardship. Multiple approaches to exerting a cooling influence have the potential to contribute to offset at least some of the projected climate disruption if deployed in the near term. Employed thoughtfully, such approaches could be used to limit global warming to well below 1° C, a level that has led to large reductions in sea ice, destabilization of ice sheets, loss of biodiversity, and transformation of ecosystems. An effective plan for avoiding “dangerous anthropogenic interference with the climate system,” would include: a) early deployment of one or more direct cooling influence(s), initially focused on offsetting amplified polar warming; b) accelerated reductions in emissions of CO2, methane and other short-lived warming agents; and c) building capacity to remove legacy GHG loadings from the atmosphere. Only the application of emergency cooling “tourniquets,” researched and applied reasonably soon to a “bleeding” Earth, have the potential to slow or reverse ongoing and increasingly severe climate disruption. Effect of Regional Marine Cloud Brightening Interventions on Climate-Tipping Elements <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023GL104314> Hirasawa, H., Hingmire, D., Singh, H., Rasch, P. J., & Mitra, P. (2023). Effect of regional marine cloud brightening interventions on climate tipping elements. *Geophysical Research Letters*, *50*(20), e2023GL104314. Abstract:It has been proposed that increasing greenhouse gas (GHG) driven climate tipping point risks may prompt consideration of solar radiation modification (SRM) climate intervention to reduce those risks. Here, we study marine cloud brightening (MCB) SRM interventions in three subtropical oceanic regions using Community Earth System Model 2 experiments. We assess the MCB impact on tipping element-related metrics to estimate the extent to which such interventions might reduce tipping element risks. Both the pattern and magnitude of the MCB cooling depend strongly on location of the MCB intervention. We find the MCB cooling effect reduces most tipping element impacts; though differences in MCB versus GHG climate response patterns mean MCB is an imperfect remedy. However, MCB applied in certain regions may exacerbate certain GHG tipping element impacts. Thus, it is crucial to carefully consider the pattern of MCB interventions and their teleconnected responses to avoid unintended climate effects. *Metals from spacecraft reentry in stratospheric aerosol particles <https://www.pnas.org/doi/full/10.1073/pnas.2313374120>* Murphy, D. M., Abou-Ghanem, M., Cziczo, D. J., Froyd, K. D., Jacquot, J., Lawler, M. J., ... & Shen, X. (2023). Metals from spacecraft reentry in stratospheric aerosol particles. *Proceedings of the National Academy of Sciences*, *120*(43), e2313374120.*Abstract: *Large increases in the number of low earth orbit satellites are projected in the coming decades [L. Schulz, K.-H. Glassmeier, *Adv. Space Res.* *67*, 1002–1025 (2021)] with perhaps 50,000 additional satellites in orbit by 2030 [GAO, Large constellations of satellites: Mitigating environmental and other effects (2022)]. When spent rocket bodies and defunct satellites reenter the atmosphere, they produce metal vapors that condense into aerosol particles that descend into the stratosphere. So far, models of spacecraft reentry have focused on understanding the hazard presented by objects that survive to the surface rather than on the fate of the metals that vaporize. Here, we show that metals that vaporized during spacecraft reentries can be clearly measured in stratospheric sulfuric acid particles. Over 20 elements from reentry were detected and were present in ratios consistent with alloys used in spacecraft. The mass of lithium, aluminum, copper, and lead from the reentry of spacecraft was found to exceed the cosmic dust influx of those metals. About 10% of stratospheric sulfuric acid particles larger than 120 nm in diameter contain aluminum and other elements from spacecraft reentry. Planned increases in the number of low earth orbit satellites within the next few decades could cause up to half of stratospheric sulfuric acid particles to contain metals from reentry. The influence of this level of metallic content on the properties of stratospheric aerosol is unknown. Solar Radiation Modification challenges decarbonization with renewable solar energy <https://egusphere.copernicus.org/preprints/2023/egusphere-2023-2337/> Baur, S., Sanderson, B. M., Séférian, R., & Terray, L. (2023). Solar Radiation Modification challenges decarbonization with renewable solar energy. *EGUsphere*, *2023*, 1-22.*Abstract:* Solar Radiation Modification (SRM) is increasingly being discussed as a potential tool to reduce global and regional temperatures to buy time for conventional carbon mitigation measures to take effect. However, most simulations to date assume SRM as an additive component to the climate change toolbox, without any physical coupling between mitigation and SRM. In this study, we analyze one aspect of this coupling: How renewable energy (RE) capacity, and therefore decarbonization rates, may be affected under SRM deployment by modification of photovoltaic (PV) and concentrated solar power (CSP) production potential. Simulated 1-hour output from the Earth System Model CNRM-ESM2-1 for scenario-based experiments are used for the assessment. We find that by the end of the century, most regions experience an increased number of low PV and CSP energy weeks per year under SAI (Stratospheric Aerosol Injections) compared to the moderately ambitiously mitigated scenario SSP245. Compared to the unmitigated SSP585 scenario, while the increase in low energy weeks is still dominant, some areas see fewer low PV or CSP energy weeks under SAI. A substantial part of the decrease in potential with SAI compared to the SSP-scenarios is compensated by optically thinner upper tropospheric clouds under SAI. Our study suggests that using SAI to reduce high-end global warming to moderate global warming could pose increased challenges for meeting energy demand with solar renewable resources. <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023EF003714> <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023GL104314> ------------------------------ COMPENDIUMFROZEN ARCTIC: Compendium of interventions to slow down, halt, and reverse the effects of climate change in the Arctic and northern regions <https://new.uarctic.org/media/to0bjpal/frozen-arctic-rra-compendium.pdf> ------------------------------ WEB POSTSClimate intervention requires international research and the Global South has contributions to make <https://illuminem.com/illuminemvoices/climate-intervention-requires-international-research-and-the-global-south-has-critical-contributions-to-make> (Illuminem)Article on Geoengineering in an Italian Newspaper <https://www.ilfattoquotidiano.it/2023/10/16/contro-la-crisi-climatica-si-valuta-il-ricorso-alla-geoingegneria-cose-e-cosa-prevede/7310307/> (FQ)*Global Concerns Over Marine Geoengineering Echo Worldwide, Signaling United Stand for Regulations <https://www.ciel.org/news/global-concerns-over-marine-geoengineering-echo-worldwide-signaling-united-stand-for-regulations/> (CIEL)* ------------------------------ *UPCOMING EVENTS*(NEW) A Conversation About Climate and Solar Geoengineering <https://environment.harvard.edu/event/conversation-about-climate-and-solar-geoengineering> | 26 October 2023*(NEW) Model Simulations of Climate Interventions Aiming to Offset Future Warming: Insights and Uncertainties by Healthy Planet Action Coalition <https://us02web.zoom.us/j/88954851189?pwd=WVZoeTBnN3kyZFoyLzYxZ1JNbDFPUT09> | 02 November 2023**Climate Engineering (GRS) <https://www.grc.org/climate-engineering-grs-conference/2024/>| 17-18 February 2024**GRC Climate Engineering 2024 <https://www.grc.org/climate-engineering-conference/2024/>| 18-23 February 2024* ------------------------------ JOB OPPORTUNITIESAssistant Professor at Texas A&M University: College of Arts & Sciences: Atmospheric Sciences <https://apply.interfolio.com/130887> | Deadline: 06 November 2023 *“The Department of Atmospheric Sciences in the College of Arts & Sciences at Texas A&M University invites applications for two full-time tenure-track assistant professor positions in the areas of (i) weather and climate risk, climate impacts, or geoengineering, (ii) applications of machine learning or artificial intelligence in weather and climate, or (iii) atmospheric turbulence, boundary layer meteorology, or urban meteorology, including high-resolution observations, modeling, or downscaling. This position is expected to begin in Fall 2024.”* Technical Director at Arctic Ice Project (AIP) <https://groups.google.com/g/geoengineering/c/5LlEkXCkdyQ> *“AIP (https://www.arcticiceproject.org <https://www.arcticiceproject.org>) is dedicated to preserving and restoring Arctic sea ice to both cool the Arctic and slow down global warming. We are in our R&D phase now to ensure our methodology is both safe for the environment and effective.”* ------------------------------ PODCASTSGlobal Climate Politics and the Dangers of Solar Geoengineering | Terra Verde <https://www.earthisland.org/journal/index.php/podcast/entry/global-climate-politics-and-the-dangers-of-solar-geoengineering> *“The politics around solar geoenigeenering — which refers to technologies that would reflect the sun’s radiation away from Earth as a means to cool the planet — have intensified in recent years. That includes the release of a new report on the subject by a little-known climate lobbying group, The Overshoot Commission, at the UN climate talks last month in New York. The report offers an alarming narrative promoting solar geoengineering as a response to the change crisis, despite the uncertainties around it, the risks it poses to both communities and the environment, and the fact that it does not address the root causes of climate change.**Dr. Carl Schleussner, head of science at Climate Analytics, joins Terra Verde host Gary Graham Hughes to offer insight into the current state of global climate politics, geoengineering lobbying by groups like The Overshoot Commission, and what it means if high level politicians are considering solar geoengineering as a climate solution.”* ------------------------------ YOUTUBE VIDEOS*Solar Radiation Modification: Governance options | C2G Carnegie Climate Governance Initiative* <https://www.youtube.com/watch?v=jKx7zI22t-c> *“What are the potential governance options available for addressing Solar Radiation Modification? Whether you are for, against, or unsure, of Solar Radiation Modification comprehensive international governance is urgently needed.”* *SRM YW Soft Launch Event in Bangladesh | SRM Youth Watch* <https://www.youtube.com/watch?v=Qeqsh6P0nYM> -- 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 on the web visit https://groups.google.com/d/msgid/geoengineering/CAHJsh9_smOrz0w3bd%2BymTUo-b8LDDn_t6TRhQUtoi2YB723SGg%40mail.gmail.com.
