title: Spectral dependence of aerosol light absorption at an urban and a remote site over the Tibetan Plateau.
abstract: We present a study of aerosol light absorption by using a 7-wavelength Aethalometer model AE33 at an urban site (Lhasa) and a remote site (Lulang) in the Tibetan Plateau. Approximately 5 times greater aerosol absorption values were observed at Lhasa (53±46Mm-1at 370nm and 20±18Mm-1at 950nm, respectively) in comparison to Lulang (15±19Mm-1at 370nm and 4±5Mm-1at 950nm, respectively). Black carbon (BC) was the dominant light absorbing aerosol component at all wavelengths. The brown carbon (BrC) absorption at 370nm is 32±15% of the total aerosol absorption at Lulang, whereas it is 8±6% at Lhasa. Higher value of absorption Ångström exponent (AAE, 370-950nm) was obtained for Lulang (1.18) than that for Lhasa (1.04) due to the presence of BrC. The AAEs (370-950nm) of BrC were directly extracted at Lulang (3.8) and Lhasa (3.3). The loading compensation parameters (k) increased with wavelengths for both sites, and lower values were obtained at Lulang than those observed at Lhasa for all wavelengths. This study underlines the relatively high percentage of BrC absorption contribution in remote area compared to urban site over the Tibetan Plateau.
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China. Electronic address: chongshu@ieecas.cn.
authors.forename: Chong-Shu
authors.initials: CS
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China. Electronic address: cao@loess.llqg.ac.cn.
authors.forename: Jun-Ji
authors.initials: JJ
authors.lastname: Cao
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
authors.forename: Ta-Feng
authors.initials: TF
authors.lastname: Hu
authors.affiliation: Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Zhen-Xing
authors.initials: ZX
authors.lastname: Shen
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Xue-Xi
authors.initials: XX
authors.lastname: Tie
authors.affiliation: School of Resource, Environmental and Chemical Engineering, NanChang University, Nanchang 330031, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Huang
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
authors.forename: Qi-Yuan
authors.initials: QY
authors.lastname: Wang
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
authors.forename: Ru-Jin
authors.initials: RJ
authors.lastname: Huang
authors.affiliation: Key Laboratory of Aerosol Chemistry & Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
authors.forename: Zhu-Zi
authors.initials: ZZ
authors.lastname: Zhao
authors.affiliation: Research and Development Department, Aerosol d.o.o., 1000 Ljubljana, Slovenia; Condensed Matter Physics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Griša
authors.initials: G
authors.lastname: Močnik
authors.affiliation: Magee Scientific Corp., Berkeley, CA 94702, USA.
authors.forename: Anthony D A
authors.initials: ADA
authors.lastname: Hansen
keywords: Black carbon; Brown carbon; Light absorption; Tibetan plateau