气候变化领域集成服务门户(CCPortal): A global model-measurement evaluation of particle light scattering coefficients at elevated relative humidity

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DOI	10.5194/acp-20-10231-2020
	A global model-measurement evaluation of particle light scattering coefficients at elevated relative humidity
	Burgos M.A.; Andrews E.; Titos G.; Benedetti A.; Bian H.; Buchard V.; Curci G.; Kipling Z.; Kirkeväg A.; Kokkola H.; Laakso A.; Letertre-Danczak J.; T. Lund M.; Matsui H.; Myhre G.; Randles C.; Schulz M.; Van Noije T.; Zhang K.; Alados-Arboledas L.; Baltensperger U.; Jefferson A.; Sherman J.; Sun J.; Weingartner E.; Zieger P.
发表日期	2020
ISSN	1680-7316
起始页码	10231
结束页码	10258
卷号	20 期号:17
英文摘要	The uptake of water by atmospheric aerosols has a pronounced effect on particle light scattering properties, which in turn are strongly dependent on the ambient relative humidity (RH). Earth system models need to account for the aerosol water uptake and its influence on light scattering in order to properly capture the overall radiative effects of aerosols. Here we present a comprehensive model measurement evaluation of the particle light scattering enhancement factor f (RH), defined as the particle light scattering coefficient at elevated RH (here set to 85 %) divided by its dry value. The comparison uses simulations from 10 Earth system models and a global dataset of surface-based in situ measurements. In general, we find a large diversity in the magnitude of predicted f (RH) amongst the different models, which can not be explained by the site types. Based on our evaluation of sea salt scattering enhancement and simulated organic mass fraction, there is a strong indication that differences in the model parameterizations of hygroscopicity and model chemistry are driving at least some of the observed diversity in simulated f (RH). Additionally, a key point is that defining dry conditions is difficult from an observational point of view and, depending on the aerosol, may influence the measured f (RH). The definition of dry also impacts our model evaluation, because several models exhibit significant water uptake between RH D0% and 40 %. The multisite average ratio between model outputs and measurements is 1.64 when RHD0% is assumed as the model dry RH and 1.16 when RHD40% is the model dry RH value. The overestimation by the models is believed to originate from the hygroscopicity parameterizations at the lower RH range which may not implement all phenomena taking place (i.e., not fully dried particles and hysteresis effects). This will be particularly relevant when a location is dominated by a deliquescent aerosol such as sea salt. Our results emphasize the need to consider the measurement conditions in such comparisons and recognize that measurements referred to as dry may not be dry in model terms. Recommendations for future model measurement evaluation and model improvements are provided. © 2020 American Institute of Physics Inc.. All rights reserved.
语种	英语
scopus关键词	aerosol; atmospheric modeling; in situ measurement; light scattering; radiative transfer; relative humidity; sea salt; water uptake
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/247548
作者单位	Department of Environmental Science, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm, Sweden; Cooperative Institute for Research in Environmental Studies, University of Colorado, Boulder, CO, United States; Andalusian Institute for Earth System Research, University of Granada, Granada, Spain; European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom; NASA/Goddard Space Flight Center, Greenbelt, MD, United States; Joint Center for Earth Systems Technology, University of Maryland, Baltimore County, MD, United States; GESTAR/Universities Space Research Association, Columbia, MD, United States; Dipartimento di Scienze Fisiche e Chimiche, Università Degli Studi Dell'Aquila, L'Aquila, Italy; Centre of Excellence Cetemps, Università Degli Studi Dell'Aquila, L'Aquila, Italy; Research Department, Norwegian Meteorological Institute, Oslo, Norway; Finnish Meteorological Institute, Atmospheric Research Centre of Eastern Finland, Kuopio, Finland; Center for Inter...
推荐引用方式 GB/T 7714	Burgos M.A.,Andrews E.,Titos G.,et al. A global model-measurement evaluation of particle light scattering coefficients at elevated relative humidity[J],2020,20(17).
APA	Burgos M.A..,Andrews E..,Titos G..,Benedetti A..,Bian H..,...&Zieger P..(2020).A global model-measurement evaluation of particle light scattering coefficients at elevated relative humidity.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(17).
MLA	Burgos M.A.,et al."A global model-measurement evaluation of particle light scattering coefficients at elevated relative humidity".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.17(2020).