Impact of solar geoengineering on temperature- attributable mortality

• 成果类型: Article
• 署名作者: Harding, Anthony; Vecchi, Gabriel A.; Yang, Wenchang; Keith, David W.
• 署名单位: University System of Georgia; Georgia Institute of Technology; Princeton University; Princeton University; University of Chicago
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-15090
• DOI: 10.1073/pnas.2401801121
• 发表日期: 2024-12-24
• 关键词: climate; science; MODEL; US

摘要

Decisions about solar geoengineering (SG) entail risk-risk tradeoffs between the direct risks of SG and SG's ability to reduce climate risks. Quantitative comparisons between these risks are needed to inform public policy. We evaluate idealized SG's effectiveness in reducing deaths from warming using two climate models and an econometric analysis of temperature- attributable mortality. We find SG's impact on temperature- attributable mortality is uneven with decreases for hotter, poorer regions and increases in cooler, richer regions. Relative to no SG, global mortality is reduced by over 400,000 deaths annually [90% CI: (-1.2 million,2.7 million)] for cooling of 1 degrees C from 2.5 degrees C above preindustrial in 2080. We find no evidence that mortality reduction achieved by SG is smaller than the reduction from equivalent cooling by emissions reductions. Combining our estimates with existing estimates of risks. We find the benefits outweigh these risks by 13 times for our central estimates, or 4 deaths per 100,000 per 1 degrees C per year [90% CI: (-11,23)]. This is not a comprehensive evaluation of the risk-risk tradeoffs around SG, yet by comparing some of the most consequential impacts on human welfare it is a useful first step. uncertainties remain and require further investigation.