气候变化领域集成服务门户(CCPortal): Disentangling the Microphysical Effects of Fire Particles on Convective Clouds Through A Case Study

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DOI	10.1029/2019JD031890
	Disentangling the Microphysical Effects of Fire Particles on Convective Clouds Through A Case Study
	Takeishi A.; Storelvmo T.; Fierce L.
发表日期	2020
ISSN	2169897X
卷号	125 期号:12
英文摘要	Aerosol emissions from forest fires may impact cloud droplet activation through an increase in particle number concentrations (“the number effect”) and also through a decrease in the hygroscopicity κ of the entire aerosol population (“the hygroscopicity effect”) when fully internal mixing is assumed in models. This study investigated these effects of fire particles on the properties of simulated deep convective clouds (DCCs), using cloud-resolving simulations with the Weather Research and Forecasting model coupled with Chemistry for a case study in a partly idealized setting. We found that the magnitude of the hygroscopicity effect was in some cases strong enough to entirely offset the number/size effect, in terms of its influence on modeled droplet and ice crystal concentrations. More specifically, in the case studied here, the droplet number concentration was reduced by about 37% or more due solely to the hygroscopicity effect. In the atmosphere, by contrast, fire particles likely have a much weaker impact on the hygroscopicity of the pre-existing background aerosol, as such a strong impact would occur only if the fire particles mixed immediately and uniformly with the background. We also show that the differences in the number of activated droplets eventually led to differences in the optical thickness of the clouds aloft, though this finding is limited to only a few hours of the initial development stage of the DCCs. These results suggest that accurately and rigorously representing aerosol mixing and κ in models is an important step toward accurately simulating aerosol-cloud interactions under the influence of fires. ©2020. The Authors.
英文关键词	aerosol activation; aerosol-cloud interaction; WRF-CHEM
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185961
作者单位	Department of Geology and Geophysics, Yale University, New Haven, CT, United States; Currently at Laboratoire d'Aérologie, University of Toulouse/CNRS, Toulouse, France; Department of Geosciences, University of Oslo, Oslo, Norway; Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, United States
推荐引用方式 GB/T 7714	Takeishi A.,Storelvmo T.,Fierce L.. Disentangling the Microphysical Effects of Fire Particles on Convective Clouds Through A Case Study[J],2020,125(12).
APA	Takeishi A.,Storelvmo T.,&Fierce L..(2020).Disentangling the Microphysical Effects of Fire Particles on Convective Clouds Through A Case Study.Journal of Geophysical Research: Atmospheres,125(12).
MLA	Takeishi A.,et al."Disentangling the Microphysical Effects of Fire Particles on Convective Clouds Through A Case Study".Journal of Geophysical Research: Atmospheres 125.12(2020).