*WEEKLY SUMMARY (27 NOVEMBER - 03 DECEMBER 2023) <https://substack.com/app-link/publications/1346479/drafts/085938a4-8b4d-4a33-af57-2eac8142ffc2?publication_id=1346479&post_id=139197216&utm_source=post-email-title&utm_campaign=email-post-title&isFreemail=false>**Subscribe to Solar Geoengineering Updates Substack here:*
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Pledge your support <https://solargeoengineeringupdates.substack.com/subscribe?utm_source=test&utm_campaign=email-checkout&next=https%3A%2F%2Fsolargeoengineeringupdates.substack.com%2Fpublish%2Fpost%2F139432824&utm_medium=email&utm_source=subscribe-widget-preamble&utm_content=139432824> DEADLINES*Call for Proposals-Grants for social science research on solar radiation modification | Deadline: 13 December 2023 <https://link.sbstck.com/redirect/406a123d-1524-41ec-b2b9-486abcf28cdf?j=eyJ1IjoiMjJrMHl3In0.wQQsFypG52typ8FI2nhnJ8eUoUIIkdCkuhmzxNYKtgE>*(NEW) Call for Papers: Special Collection "Towards a Risk-Risk-Assessment of Solar Radiation Modification" <https://academic.oup.com/oocc/pages/solar-radiation-modification?login=false> | Deadline for manuscript submissions: 31 May 2024 ------------------------------ RESEARCH PAPERSEvidence that deliberate marine cloud brightening can be more effective than previously thought <https://www.researchsquare.com/article/rs-3291831/v1> Chen, Y., Haywood, J., Wang, Y., Malavelle, F., Jordan, G., Peace, A., ... & Lohmann, U. (2023). Evidence that deliberate marine cloud brightening can be more effective than previously thought. *UMBC Faculty Collection*. *Abstract*With global warming currently standing at approximately + 1.2 °C, climate change is a pressing global issue. Marine cloud brightening (MCB) proposes injecting aerosols into marine clouds to enhance their reflectivity and thereby planetary albedo. However, because it is unclear how aerosols influence clouds, especially cloud cover, both climate projections and the effectiveness of MCB remain uncertain. Here, we use volcanic eruptions to quantify the aerosol fingerprint on tropical marine clouds. We observe a large enhancement in reflected sunlight, mainly due to an aerosol-induced increase in cloud cover. This observational evidence of a strong aerosol impact suggests that the Earth’s climate is highly sensitive to external forcing mechanisms, but also that mitigation of global warming via MCB is more plausible than current climate models suggest. Our results suggest that the best efficacy for MCB practice is to seed clouds in humid and stable meteorological conditions. Responses of Extreme Climates in South Asia under a G6sulfur Scenario of Climate Engineering <https://www.mdpi.com/2073-4433/14/10/1490> Wang, J., Zhang, Z., Crabbe, M. J. C., & Das, L. C. (2023). Responses of Extreme Climates in South Asia under a G6sulfur Scenario of Climate Engineering. *Atmosphere*, *14*(10), 1490.*Abstract*Under global warming scenarios, extreme climate events in South Asia will occur more frequently which will seriously threaten the safety of local residents. South Asia faces dual pressures of the obligation of carbon emissions reduction globally and the demand for a better life for huge populations. Stratospheric Aerosol Injection (SAI) climate engineering provides a potential solution to this dilemma. We compared the evolution of 12 climate extreme indices under historical scenarios, two future scenarios (SSP245, SSP585) and an implementation scenario of SAI climate engineering (G6sulfur). We showed that the intensity and frequency of extreme climates under a G6sulfur scenario would be significantly higher than those under historical scenarios, and that the difference in extreme climates under three scenarios (SSP245, SSP585, and G6sulfur) would be widely varying, with some indices being considerably mitigated while others would reflect a worse set of circumstances than would be the case without SAI climate engineering. Therefore, SAI climate engineering is not an effective tool to mitigate future climate extremes in South Asia under global warming scenarios. Stratospheric Sulfate Aerosols Impacts on West African Monsoon Precipitation Using GeoMIP Models <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023EF003779> Bonou, F., Da‐Allada, C. Y., Baloitcha, E., Alamou, E., Biao, E. I., Zandagba, J., ... & Tilmes, S. (2023). Stratospheric sulfate aerosols impacts on West African monsoon precipitation using GeoMIP models. *Earth's Future*, *11*(11), e2023EF003779.*Abstract*Stratospheric Aerosol Geoengineering (SAG) is proposed to offset global warming; however, the use of this approach can an impact on the hydrological cycle. We used simulations from Coupled Model Intercomparison Project (CMIP5) and Geoengineering Model Intercomparison Project (G3 simulation) to analyze the impacts of SAG on precipitation (P) and to determine its responsible causes in West Africa and Sahel region. CMIP5 historical data were first validated, the results obtained are consistent with observational data. Under the Representative Concentration Pathway scenario RCP4.5, a slight increase is found in the West Africa Region relative to present-day climate. The dynamic processes especially, the monsoon shifts are responsible for this precipitation change. Under RCP4.5, during the monsoon period, reductions in P are 0.86%, 0.80% relative to the present-day climate in the Northern and Southern Sahel, respectively, while precipitation is increased by 1.04% in the West African Region. Under SAG, we find a 3.71% decrease of precipitation in the West African Region while the precipitation decrease is 17.4% and 8.47% respectively in the North Sahel and South Sahel. This decrease in monsoon precipitation is mainly explained by changes in dynamics, which lead to weakened monsoon circulation and a shift in the distribution of monsoon precipitation. This result suggests that SAG deployment to balance all warming can be harmful to rainfall in WAR if the amount of SO2 to be injected into this tropical area is not taken into consideration. How may solar geoengineering impact global prospects for climate change mitigation? <https://academic.oup.com/oxrep/article-abstract/39/4/828/7425305?redirectedFrom=fulltext> Ricke, K., & Harding, A. (2023). How may solar geoengineering impact global prospects for climate change mitigation?. *Oxford Review of Economic Policy*, *39*(4), 828-841.*Abstract*As disruptions from climate change increase, so will the urgency to find shorter-term approaches to ameliorating its harms. This may include calls to implement solar geoengineering, an approach to cooling the planet by reflecting incoming sunlight back to space. While the exact effects of solar geoengineering are still highly uncertain, physical science to date suggests that it may be effective at reducing many aspects of climate change in the short term. One of the biggest concerns about solar geoengineering is the extent to which it may interfere with crucial emissions reductions policies, i.e. mitigation. There are multiple channels by which geoengineering could alter mitigation pathways, both financial and behavioural. Here we define three such linkages and present the evidence available to constrain their potential magnitudes. Because solar geoengineering is not a substitute for mitigation, policies to develop or implement technologies that could be used to carry it out should be designed to accentuate its complementary nature to mitigation and deter the possibility it is used to delay decarbonizing the economy. Reduced Ice Loss From Greenland Under Stratospheric Aerosol Injection <https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023JF007112> Moore, J. C., Greve, R., Yue, C., Zwinger, T., Gillet‐Chaulet, F., & Zhao, L. (2023). Reduced ice loss from Greenland under stratospheric aerosol injection. *Journal of Geophysical Research: Earth Surface*, *128*(11), e2023JF007112.*Abstract*Sea level rise (SLR) due to surface melt and to dynamic losses from the ice sheets—that is via accelerated flow of glaciers into the sea—is something that may be potentially mitigated by cooling the ice sheet and oceans via solar geoengineering. We use two ice dynamic models driven by changes in surface mass balance (SMB) from four climate models to estimate the SLR contribution from the Greenland ice sheet under the Intergovernmental Panel on Climate Change (IPCC) Representative Concentration Pathway (RCP) 4.5, and 8.5, and Geoengineering Model Intercomparison Project G4 scenarios. The G4 scenario adds 5 Tg/yr sulfate aerosols to the equatorial lower stratosphere (equivalent of 1/4 the 1991 Mt Pinatubo SO2 eruption) to the IPCC RCP4.5 scenario, which itself approximates the greenhouse gas emission commitments agreed in Paris in 2015. Over the 2020–2090 period, mass loss under G4 is about 31%–38% that under RCP4.5, which is 36%–48% lower than under RCP8.5. Ice lost across the grounding line under both G4 and RCP4.5 is reduced in the future as the termini of many southeast Greenland outlets retreat onto bedrock above sea level. Glaciers with large low-lying catchments in the west, north, and northeast of Greenland (e.g., Jakobshavn, 79N, Zachariae Isstrøm, and Petermann glaciers) discharge more ice from the ice-sheet interior under RCP4.5 than under G4. Although calving losses vary much more than the SMB difference between ice dynamic models, both models point to significant ice discharge losses of between 15% and 42% across the scenarios. [image: Figure 1] <https://www.researchsquare.com/article/rs-3291831/v1> ------------------------------ WEB POSTSInés Camilloni contributes to UNESCO ethics report on SRM <https://www.degrees.ngo/ines-camilloni-contributes-to-unesco-ethics-report-on-srm/> (The Degrees Initiative) ------------------------------ REPORTSReport of The World Commission on the Ethics of Scientific Knowledge and Technology (COMEST) on the Ethics of Climate Engineering <https://unesdoc.unesco.org/ark:/48223/pf0000386677> (UNESCO) ------------------------------ *UPCOMING EVENTS*(NEW) SilverLining Reception: Intergenerational Dialogue on Near-term Climate risk and Intervention <https://www.silverlining.ngo/silverlining-at-cop28> | 05 December 2023 | Dubai(NEW) A Parasol for Mother Earth? Geoengineering for Climate Change at Sheridan College Museum of Discovery Science, Canada <https://www.thesheridanpress.com/news/local/college-science-lecture-will-discuss-geoengineering/article_6c21981c-8fe8-11ee-b479-0fa3ea3cbb7c.html> | 06 December 2023*104th Annual Meeting by American Meteorological Society <https://ams.confex.com/ams/104ANNUAL/meetingapp.cgi/Program/1743> | 28 January 2024 - 01 February 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* ------------------------------ PODCASTSA radical solution to address climate change, with David Keith | Big Brains <https://news.uchicago.edu/radical-solution-address-climate-change-david-keith> *“Solar geoengineering technology holds possibilities and pitfalls, renowned scientist argues.**Climate change can feel like an impossible crisis these days. Every week there is some new report about the irreversible damage we’re doing to our planet and the havoc it will bring to people’s lives. We all know cutting emissions is the solution, yet governments and companies seem no closer to meeting the goals that scientists say we must hit. It can feel hopeless.**There is one possible controversial solution to climate change many in the mainstream haven’t discussed. It’s so controversial, in fact, that some experts say we shouldn’t even be discussing it. But University of Chicago Professor David Keith says we need to talk about it. It’s called solar geoengineering—the process in which you reflect a small fraction of sunlight back into space using aerosols. As the founding director of the Climate Systems Engineering Initiative at UChicago, Keith is leading a team that will research solar geoengineering and other novel solutions to climate change.”* ------------------------------ YOUTUBE VIDEOS*Why it is important for the Global South to engage in governance discussions of SRM. | SRM YOUTH WATCH* <https://www.youtube.com/watch?v=h4m1C85iBEY> *"Engagement in SRM goverance discussions does not mean support of SRM"* *TechEthos - Climate Engineering and Ethical Issues | Ecsite Executive Office* <https://www.youtube.com/watch?v=gMUvIO8JF6U> *“What are some of the most pressing ethical issues related to climate engineering? What are some key regulatory challenges related to climate engineering technologies, such as carbon removal? What role should climate engineering play in meeting the EU’s target of net zero by 2050? Bennet Francis, Dominic Lenzi, and Michel Bourban (UT) share their thoughts on climate engineering.”* A radical solution to address climate change, with David Keith | The University of Chicago <https://www.youtube.com/watch?v=jWHb0iEAxGY> *“Solar geoengineering technology holds possibilities and pitfalls, renowned scientist argues Climate change can feel like an impossible crisis these days. Every week there is some new report about the irreversible damage we’re doing to our planet and the havoc it will bring to people’s lives. We all know cutting emissions is the solution, yet governments and companies seem no closer to meeting the goals that scientists say we must hit. It can feel hopeless. There is one possible controversial solution to climate change many in the mainstream haven’t discussed. It’s so controversial, in fact, that some experts say we shouldn’t even be discussing it. But University of Chicago Professor David Keith says we need to talk about it. It’s called solar geoengineering—the process in which you reflect a small fraction of sunlight back into space using aerosols. As the founding director of the Climate Systems Engineering Initiative at UChicago, Keith is leading a team that will research solar geoengineering and other novel solutions to climate change.”* The Plastic Sea of Almeria: Proof of Concept Solar Radiation Management The Giant Sun Reflector MEER | Climate Alert <https://www.youtube.com/watch?v=2gRbqIsDfTg> ------------------------------ Share Solar Geoengineering Updates <https://solargeoengineeringupdates.substack.com/?utm_source=substack&utm_medium=email&utm_content=share&action=share> -- 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 geoengineering+unsubscr...@googlegroups.com. 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