干旱区生态环境知识资源中心(Arid): A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties

Arid

DOI	10.5194/acp-21-13031-2021
	A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties
	Titos, Gloria; Burgos, Maria A.; Zieger, Paul; Alados-Arboledas, Lucas; Baltensperger, Urs; Jefferson, Anne; Sherman, James; Weingartner, Ernest; Henzing, Bas; Luoma, Krista; O'Dowd, Colin; Wiedensohler, Alfred; Andrews, Elisabeth
通讯作者	Titos, G (corresponding author), Univ Granada, Andalusian Inst Earth Syst Res, Granada 18006, Spain. ; Titos, G (corresponding author), Univ Granada, Dept Appl Phys, Granada 18071, Spain.
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
ISSN	1680-7316
EISSN	1680-7324
出版年	2021
卷号	21 期号:17 页码:13031-13050
英文摘要	The scattering and backscattering enhancement factors (f (RH) and f(b)(RH)) describe how aerosol particle light scattering and backscattering, respectively, change with relative humidity (RH). They are important parameters in estimating direct aerosol radiative forcing (DARF). In this study we use the dataset presented in Burgos et al. (2019) that compiles f(RH) and f(b)(RH) measurements at three wavelengths (i.e., 450, 550 and 700 nm) performed with tandem nephelometer systems at multiple sites around the world. We present an overview of f (RH) and f(b)(RH) based on both long-term and campaign observations from 23 sites representing a range of aerosol types. The scattering enhancement shows a strong variability from site to site, with no clear pattern with respect to the total scattering coefficient. In general, higher f(RH) is observed at Arctic and marine sites, while lower values are found at urban and desert sites, although a consistent pattern as a function of site type is not observed. The backscattering enhancement f(b)(RH) is consistently lower than f(RH) at all sites, with the difference between f(RH) and f(b)(RH) increasing for aerosol with higher f(RH). This is consistent with Mie theory, which predicts higher enhancement of the light scattering in the forward than in the backward direction as the particle takes up water. Our results show that the scattering enhancement is higher for PM1 than PM10 at most sites, which is also supported by theory due to the change in scattering efficiency with the size parameter that relates particle size and the wavelength of incident light. At marine-influenced sites this difference is enhanced when coarse particles (likely sea salt) predominate. For most sites, f (RH) is observed to increase with increasing wavelength, except at sites with a known dust influence where the spectral dependence of f (RH) is found to be low or even exhibit the opposite pattern. The impact of RH on aerosol properties used to calculate radiative forcing (e.g., single-scattering albedo, omega(0), and backscattered fraction, b) is evaluated. The single-scattering albedo generally increases with RH, while b decreases. The net effect of aerosol hygroscopicity on radiative forcing efficiency (RFE) is an increase in the absolute forcing effect (negative sign) by a factor of up to 4 at RH = 90% compared to dry conditions (RH < 40 %). Because of the scarcity of scattering enhancement measurements, an attempt was made to use other more commonly available aerosol parameters (i.e., omega(0) and scattering Angstrom exponent, ffsp) to parameterize f (RH). The majority of sites (75 %) showed a consistent trend with omega(0) (higher f (RH D 85 %) for higher omega(0)), while no clear pattern was observed between f (RH = 85 %) and ffsp. This suggests that aerosol omega(0) is more promising than ffsp as a surrogate for the scattering enhancement factor, although neither parameter is ideal. Nonetheless, the qualitative relationship observed between omega(0) and f (RH) could serve as a constraint on global model simulations.
类型	Article
语种	英语
开放获取类型	gold, Green Published, Green Accepted, Green Submitted
收录类别	SCI-E
WOS记录号	WOS:000692941900004
WOS关键词	FILTER-BASED MEASUREMENTS ; RELATIVE-HUMIDITY ; HUMIDIFICATION FACTORS ; ANTHROPOGENIC SULFATE ; RADIATIVE PROPERTIES ; LIDAR MEASUREMENTS ; ORGANIC AEROSOL ; EXTINCTION ; ABSORPTION ; SURFACE
WOS类目	Environmental Sciences ; Meteorology & Atmospheric Sciences
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/362650
作者单位	[Titos, Gloria; Alados-Arboledas, Lucas] Univ Granada, Andalusian Inst Earth Syst Res, Granada 18006, Spain; [Titos, Gloria; Alados-Arboledas, Lucas] Univ Granada, Dept Appl Phys, Granada 18071, Spain; [Burgos, Maria A.; Zieger, Paul] Stockholm Univ, Dept Environm Sci, Stockholm, Sweden; [Burgos, Maria A.; Zieger, Paul] Stockholm Univ, Bolin Ctr Climate Res, Stockholm, Sweden; [Baltensperger, Urs; Weingartner, Ernest] Paul Scherrer Inst, Lab Atmospher Chem, Villigen, Switzerland; [Jefferson, Anne; Andrews, Elisabeth] Univ Colorado, Cooperat Inst Res Environm Studies, Boulder, CO 80309 USA; [Sherman, James] Appalachian State Univ, Dept Phys & Astron, Boone, NC 28608 USA; [Henzing, Bas] Netherlands Org Appl Sci Res TNO, Princetonlaan 6, NL-3584 Utrecht, Netherlands; [Luoma, Krista] Univ Helsinki, Fac Sci, Inst Atmospher & Earth Syst Res Phys, POB 68, Helsinki 00014, Finland; [O'Dowd, Colin] Natl Univ Ireland Galway, Ryan Inst Ctr Climate & Air Pollut Studies, Sch Phys, Univ Rd, Galway H91 CF50, Ireland; [Wi...
推荐引用方式 GB/T 7714	Titos, Gloria,Burgos, Maria A.,Zieger, Paul,et al. A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties[J],2021,21(17):13031-13050.
APA	Titos, Gloria.,Burgos, Maria A..,Zieger, Paul.,Alados-Arboledas, Lucas.,Baltensperger, Urs.,...&Andrews, Elisabeth.(2021).A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(17),13031-13050.
MLA	Titos, Gloria,et al."A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.17(2021):13031-13050.