气候变化领域集成服务门户(CCPortal): Harnessing stratospheric diffusion barriers for enhanced climate geoengineering

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DOI	10.5194/acp-21-8845-2021
	Harnessing stratospheric diffusion barriers for enhanced climate geoengineering
	Aksamit N.O.; Kravitz B.; MacMartin D.G.; Haller G.
发表日期	2021
ISSN	1680-7316
起始页码	8845
结束页码	8861
卷号	21 期号:11
英文摘要	Stratospheric sulfate aerosol geoengineering is a proposed method to temporarily intervene in the climate system to increase the reflectance of shortwave radiation and reduce mean global temperature. In previous climate modeling studies, choosing injection locations for geoengineering aerosols has, thus far, only utilized the average dynamics of stratospheric wind fields instead of accounting for the essential role of time-varying material transport barriers in turbulent atmospheric flows. Here we conduct the first analysis of sulfate aerosol dispersion in the stratosphere, comparing what is now a standard fixed-injection scheme with time-varying injection locations that harness short-term stratospheric diffusion barriers. We show how diffusive transport barriers can quickly be identified, and we provide an automated injection location selection algorithm using short forecast and reanalysis data. Within the first 7 d days of transport, the dynamics-based approach is able to produce particle distributions with greater global coverage than fixed-site methods with fewer injections. Additionally, this enhanced dispersion slows aerosol microphysical growth and can reduce the effective radii of aerosols up to 200-300 d after injection. While the long-term dynamics of aerosol dispersion are accurately predicted with transport barriers calculated from short forecasts, the long-term influence on radiative forcing is more difficult to predict and warrants deeper investigation. Statistically significant changes in radiative forcing at timescales beyond the forecasting window showed mixed results, potentially increasing or decreasing forcing after 1 year when compared to fixed injections. We conclude that future feasibility studies of geoengineering should consider the cooling benefits possible by strategically injecting sulfate aerosols at optimized time-varying locations. Our method of utilizing time-varying attracting and repelling structures shows great promise for identifying optimal dispersion locations, and radiative forcing impacts can be improved by considering additional meteorological variables. © Copyright:
语种	英语
scopus关键词	aerosol; diffusion; meteorology; radiative forcing; stratosphere; sulfate
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/246817
作者单位	Institute for Mechanical Systems, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland; Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, IN, United States; Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, United States; Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, United States
推荐引用方式 GB/T 7714	Aksamit N.O.,Kravitz B.,MacMartin D.G.,et al. Harnessing stratospheric diffusion barriers for enhanced climate geoengineering[J],2021,21(11).
APA	Aksamit N.O.,Kravitz B.,MacMartin D.G.,&Haller G..(2021).Harnessing stratospheric diffusion barriers for enhanced climate geoengineering.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(11).
MLA	Aksamit N.O.,et al."Harnessing stratospheric diffusion barriers for enhanced climate geoengineering".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.11(2021).