气候变化领域集成服务门户(CCPortal): Optical properties of Central Asian aerosol relevant for spaceborne lidar applications and aerosol typing at 355 and 532 nm

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DOI	10.5194/acp-20-9265-2020
	Optical properties of Central Asian aerosol relevant for spaceborne lidar applications and aerosol typing at 355 and 532 nm
	Hofer J.; Ansmann A.; Althausen D.; Engelmann R.; Baars H.; Wadinga Fomba K.; Wandinger U.; Abdullaev S.F.; Makhmudov A.N.
发表日期	2020
ISSN	1680-7316
起始页码	9265
结束页码	9280
卷号	20 期号:15
英文摘要	For the first time, a dense data set of particle extinction-to-backscatter ratios (lidar ratios), linear depolarization ratios, and backscatter- and extinction-related Ångström exponents for a Central Asian site are presented. The observations were performed with a continuously running multiwavelength polarization Raman lidar at Dushanbe, Tajikistan, during an 18-month campaign (March 2015 to August 2016). The presented seasonally resolved observations fill an important gap in the database of aerosol optical properties used in aerosol typing efforts with spaceborne lidars and ground-based lidar networks. Lidar ratios and depolarization ratios are also basic input parameters in spaceborne lidar data analyses and in efforts to harmonize long-term observations with different space lidar systems operated at either 355 or 532 nm. As a general result, the found optical properties reflect the large range of occurring aerosol mixtures consisting of long-range-transported dust (from the Middle East and the Sahara), regional desert, soil, and salt dust, and anthropogenic pollution. The full range from highly polluted to pure dust situations could be observed. Typical dust depolarization ratios of 0.23-0.29 (355 nm) and 0.30-0.35 (532 nm) were observed. In contrast, comparably low lidar ratios were found. Dust lidar ratios at 532 nm accumulated around 35-40 sr and were even lower for regional background dust conditions (20-30 sr). Detailed correlation studies (e.g., lidar ratio vs. depolarization ratios, Ångström exponent vs. lidar ratio and vs. depolarization ratio) are presented to illuminate the complex relationships between the observed optical properties and to identify the contributions of anthropogenic haze, dust, and background aerosol to the overall aerosol mixtures found within the 18-month campaign. The observation of 532 nm lidar ratios (25 sr) and depolarization ratios (around 15 %-20 %) in layers with very low particle extinction coefficient (30 sr) suggests that direct emission and emission of resuspended salt dust (initially originated from numerous desiccating lakes and the Aralkum desert) have a sensitive impact on the aerosol background optical properties over Dushanbe. © 2020 Author(s).
语种	英语
scopus关键词	aerosol property; backscatter; data set; dust; lidar; long range transport; optical property; polarization; Central Asia; Dushanbe; Tajikistan
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/247600
作者单位	Leibniz Institute for Tropospheric Research, Leipzig, Germany; Physical Technical Institute, Academy of Sciences of Tajikistan, Dushanbe, Tajikistan
推荐引用方式 GB/T 7714	Hofer J.,Ansmann A.,Althausen D.,et al. Optical properties of Central Asian aerosol relevant for spaceborne lidar applications and aerosol typing at 355 and 532 nm[J],2020,20(15).
APA	Hofer J..,Ansmann A..,Althausen D..,Engelmann R..,Baars H..,...&Makhmudov A.N..(2020).Optical properties of Central Asian aerosol relevant for spaceborne lidar applications and aerosol typing at 355 and 532 nm.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(15).
MLA	Hofer J.,et al."Optical properties of Central Asian aerosol relevant for spaceborne lidar applications and aerosol typing at 355 and 532 nm".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.15(2020).