title: New insights into trace elements deposition in the snow packs at remote alpine glaciers in the northern Tibetan Plateau, China.
abstract: Trace element pollution resulting from anthropogenic emissions is evident throughout most of the atmosphere and has the potential to create environmental and health risks. In this study we investigated trace element deposition in the snowpacks at two different locations in the northern Tibetan Plateau, including the Laohugou (LHG) and the Tanggula (TGL) glacier basins, and its related atmospheric pollution information in these glacier areas, mainly focusing on 18 trace elements (Li, Be, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Nb, Mo, Cd, Sb, Cs, Ba, Tl, and Pb). The results clearly demonstrate that pronounced increases of both concentrations and crustal enrichment factors (EFs) are observed in the snowpack at the TGL glacier basin compared to that of the LHG glacier basin, with the highest EFs for Sb and Zn in the TGL basin, whereas with the highest EFs for Sb and Cd in the LHG basin. Compared with other studies in the Tibetan Plateau and surrounding regions, trace element concentration showed gradually decreasing trend from Himalayan regions (southern Tibetan Plateau) to the TGL basin (central Tibetan Plateau), and to the LHG basin (northern Tibetan Plateau), which probably implied the significant influence of atmospheric trace element transport from south Asia to the central Tibetan Plateau. Moreover, EF calculations at two sites showed that most of the heavy metals (e.g., Cu, Zn, Mo, Cd, Sb, and Pb) were from anthropogenic sources and some other elements (e.g., Li, Rb, and Ba) were mainly originated from crustal sources. MODIS atmospheric optical depth (AOD) fields derived using the Deep Blue algorithm and CALIOP/CALIPSO transect showed significant influence of atmospheric pollutant transport from south Asia to the Tibetan Plateau, which probably caused the increased concentrations and EFs of trace element deposition in the snowpack on the TGL glacier basin.
authors.affiliation: State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China. Electronic address: dongzhiwen@lzb.ac.cn.
authors.forename: Zhiwen
authors.initials: Z
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China. Electronic address: shichang.kang@lzb.ac.cn.
authors.forename: Shichang
authors.initials: S
authors.lastname: Kang
authors.affiliation: State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; Qilian Mountain Glacier and Ecological Environment Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Qin
authors.affiliation: State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Dahe
authors.initials: D
authors.lastname: Qin
authors.affiliation: State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Jiawen
authors.initials: J
authors.lastname: Ren
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002681:China; D004784:Environmental Monitoring; D046448:Ice Cover / Q000737:chemistry*; D012914:Snow; D018609:Tibet; D014131:Trace Elements / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D014131:Trace Elements
keywords: Concentration; Glacier snowpack; Northern Tibetan Plateau; Source; Trace element