气候变化领域集成服务门户(CCPortal): Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy - Part 1: Intercomparison of modal and sectional aerosol modules

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DOI	10.5194/acp-22-93-2022
	Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy - Part 1: Intercomparison of modal and sectional aerosol modules
	Laakso, Anton; Niemeier, Ulrike; Visioni, Daniele; Tilmes, Simone; Kokkola, Harri
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	93
结束页码	118
卷号	22 期号:1 页码:26
英文摘要	Injecting sulfur dioxide into the stratosphere with the intent to create an artificial reflective aerosol layer is one of the most studied options for solar radiation management. Previous modelling studies have shown that stratospheric sulfur injections have the potential to compensate for the greenhouse-gas-induced warming at the global scale. However, there is significant diversity in the modelled radiative forcing from stratospheric aerosols depending on the model and on which strategy is used to inject sulfur into the stratosphere. Until now, it has not been clear how the evolution of the aerosols and their resulting radiative forcing depends on the aerosol microphysical scheme used - that is, if aerosols are represented by a modal or sectional distribution. Here, we have studied different spatio-temporal injection strategies with different injection magnitudes using the aerosolclimate model ECHAM-HAMMOZ with two aerosol microphysical modules: the sectional module SALSA (Sectional Aerosol module for Large Scale Applications) and the modal module M7. We found significant differences in the model responses depending on the aerosol microphysical module used. In a case where SO2 was injected continuously in the equatorial stratosphere, simulations with SALSA produced an 88 %-154% higher all-sky net radiative forcing than simulations with M7 for injection rates from 1 to 100 Tg(S) yr(-1). These large differences are identified to be caused by two main factors. First, the competition between nucleation and condensation: while injected sulfur tends to produce new particles at the expense of gaseous sulfuric acid condensing on pre-existing particles in the SALSA module, most of the gaseous sulfuric acid partitions to particles via condensation at the expense of new particle formation in the M7 module. Thus, the effective radii of stratospheric aerosols were 10 %-52% larger in M7 than in SALSA, depending on the injection rate and strategy. Second, the treatment of the modal size distribution in M7 limits the growth of the accumulation mode which results in a local minimum in the aerosol number size distribution between the accumulation and coarse modes. This local minimum is in the size range where the scattering of solar radiation is most efficient. We also found that different spatial-temporal injection strategies have a significant impact on the magnitude and zonal distribution of radiative forcing. Based on simulations with various injection rates using SALSA, the most efficient studied injection strategy produced a 33 %-42% radiative forcing compared with the least efficient strategy, whereas simulations with M7 showed an even larger difference of 48 %-116 %. Differences in zonal mean radiative forcing were even larger than that. We also show that a consequent stratospheric heating and its impact on the quasi-biennial oscillation depend on both the injection strategy and the aerosol microphysical model. Overall, these results highlight the crucial impact of aerosol microphysics on the physical properties of stratospheric aerosol which, in turn, causes significant uncertainties in estimating the climate impacts of stratospheric sulfur injections.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000739363400001
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/273274
作者单位	Finnish Meteorological Institute; Max Planck Society; Cornell University; National Center Atmospheric Research (NCAR) - USA
推荐引用方式 GB/T 7714	Laakso, Anton,Niemeier, Ulrike,Visioni, Daniele,et al. Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy - Part 1: Intercomparison of modal and sectional aerosol modules[J],2022,22(1):26.
APA	Laakso, Anton,Niemeier, Ulrike,Visioni, Daniele,Tilmes, Simone,&Kokkola, Harri.(2022).Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy - Part 1: Intercomparison of modal and sectional aerosol modules.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(1),26.
MLA	Laakso, Anton,et al."Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy - Part 1: Intercomparison of modal and sectional aerosol modules".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.1(2022):26.