气候变化领域集成服务门户(CCPortal): Aerosol particle characteristics measured in the United Arab Emirates and their response to mixing in the boundary layer

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DOI	10.5194/acp-22-481-2022
	Aerosol particle characteristics measured in the United Arab Emirates and their response to mixing in the boundary layer
	Kesti, Jutta; Backman, John; O'Connor, Ewan J.; Hirsikko, Anne; Asmi, Eija; Aurela, Minna; Makkonen, Ulla; Filioglou, Maria; Komppula, Mika; Korhonen, Hannele; Lihavainen, Heikki
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	481
结束页码	503
卷号	22 期号:1 页码:23
英文摘要	Aerosol particles play an important role in the microphysics of clouds and hence in their likelihood to precipitate. In the changing climate already-dry areas such as the United Arab Emirates (UAE) are predicted to become even drier. Comprehensive observations of the daily and seasonal variation in aerosol particle properties in such locations are required, reducing the uncertainty in such predictions. We analyse observations from a 1-year measurement campaign at a background location in the United Arab Emirates to investigate the properties of aerosol particles in this region, study the impact of boundary layer mixing on background aerosol particle properties measured at the surface, and study the temporal evolution of the aerosol particle cloud formation potential in the region. We used in situ aerosol particle measurements to characterise the aerosol particle composition, size, number, and cloud condensation nuclei (CCN) properties; in situ SO2 measurements as an anthropogenic signature; and a long-range scanning Doppler lidar to provide vertical profiles of the horizontal wind and turbulent properties to monitor the evolution of the boundary layer. Anthropogenic sulfate dominated the aerosol particle mass composition in this location. There was a clear diurnal cycle in the surface wind direction, which had a strong impact on aerosol particle total number concentration, SO2 concentration, and black carbon mass concentration. Local sources were the predominant source of black carbon as concentrations clearly depended on the presence of turbulent mixing, with much higher values during calm nights. The measured concentrations of SO2, instead, were highly dependent on the surface wind direction as well as on the depth of the boundary layer when entrainment from the advected elevated layers occurred. The wind direction at the surface or of the elevated layer suggests that the oil refineries and the cities of Dubai and Abu Dhabi and other coastal conurbations were the remote sources of SO2. We observed new-aerosol-particle formation events almost every day (on 4 d out of 5 on average). Calm nights had the highest CCN number concentrations and lowest kappa values and activation fractions. We did not observe any clear dependence of CCN number concentration and kappa parameter on the height of the daytime boundary layer, whereas the activation fraction did show a slight increase with increasing boundary layer height due to the change in the shape of the aerosol particle size distribution where the relative portion of larger aerosol particles increased with increasing boundary layer height. We believe that this indicates that size is more important than chemistry for aerosol particle CCN activation at this site. The combination of instrumentation used in this campaign enabled us to identify periods when anthropogenic pollution from remote sources that had been transported in elevated layers was present and had been mixed down to the surface in the growing boundary layer.
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:000746439800001
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/273628
作者单位	Finnish Meteorological Institute; Finnish Meteorological Institute
推荐引用方式 GB/T 7714	Kesti, Jutta,Backman, John,O'Connor, Ewan J.,et al. Aerosol particle characteristics measured in the United Arab Emirates and their response to mixing in the boundary layer[J],2022,22(1):23.
APA	Kesti, Jutta.,Backman, John.,O'Connor, Ewan J..,Hirsikko, Anne.,Asmi, Eija.,...&Lihavainen, Heikki.(2022).Aerosol particle characteristics measured in the United Arab Emirates and their response to mixing in the boundary layer.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(1),23.
MLA	Kesti, Jutta,et al."Aerosol particle characteristics measured in the United Arab Emirates and their response to mixing in the boundary layer".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.1(2022):23.