Regional Climate Impacts of Stabilizing Global Warming at 1.5 K Using Solar Geoengineering

• Published in: Earth's future Vol. 6; no. 2; pp. 230 - 251
• Main Authors: Jones, Anthony C., Hawcroft, Matthew K., Haywood, James M., Jones, Andy, Guo, Xiaoran, Moore, John C.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA Wiley Periodicals, Inc 01.02.2018; John Wiley & Sons, Inc
• Subjects: Amazon; Arctic sea ice; Climate change; Climate effects; Climate models; Extreme weather; Galvanizing; Geoengineering; Global climate; Global temperatures; Global warming; Greenhouse effect; Greenhouse gases; Heat waves; Heatwaves; Hydrology; Mean temperatures; Mitigation; Polar environments; Regional climates; River basins; Sea level rise; Storms; Temperature
• ISSN: 2328-4277; 2328-4277
• DOI: 10.1002/2017EF000720

The 2015 Paris Agreement aims to limit global warming to well below 2 K above preindustrial levels, and to pursue efforts to limit global warming to 1.5 K, in order to avert dangerous climate change. However, current greenhouse gas emissions targets are more compatible with scenarios exhibiting end‐of‐century global warming of 2.6–3.1 K, in clear contradiction to the 1.5 K target. In this study, we use a global climate model to investigate the climatic impacts of using solar geoengineering by stratospheric aerosol injection to stabilize global‐mean temperature at 1.5 K for the duration of the 21st century against three scenarios spanning the range of plausible greenhouse gas mitigation pathways (RCP2.6, RCP4.5, and RCP8.5). In addition to stabilizing global mean temperature and offsetting both Arctic sea‐ice loss and thermosteric sea‐level rise, we find that solar geoengineering could effectively counteract enhancements to the frequency of extreme storms in the North Atlantic and heatwaves in Europe, but would be less effective at counteracting hydrological changes in the Amazon basin and North Atlantic storm track displacement. In summary, solar geoengineering may reduce global mean impacts but is an imperfect solution at the regional level, where the effects of climate change are experienced. Our results should galvanize research into the regionality of climate responses to solar geoengineering. Key Points We perform simulations in which solar geoengineering is used to stabilize global warming at 1.5 K above preindustrial levels Enhanced storm surge activity and heatwave increases under global warming are effectively counteracted by solar geoengineering Solar geoengineering does little to counteract Amazonian hydrological changes and North Atlantic storm track displacement