Characteristics of dust aerosols and identification of dust sources in Xinjiang, China. (1st October 2021)

• Record Type: Journal Article
• Authors: Liu, Jie; Ding, Jianli; Rexiding, Mayila; Li, Xiaohang; Zhang, Junyong; Ran, Si; Bao, Qingling; Ge, Xiangyu
• Is Part Of: Atmospheric environment. Volume 262(2021)
• Publication Date: 2021-10-01
• Subjects: Arid area -- Dust aerosols -- Dust sources -- Dust deposition fluxes; Air -- Pollution -- Periodicals; Air -- Pollution -- Meteorological aspects -- Periodicals; 551.51
• DOI: 10.1016/j.atmosenv.2021.118651
• Languages: English
• ISSNs: 1352-2310

Abstract

Abstract: Changes in atmospheric particulate matter content directly affect the Earth-atmosphere system balance and climate change and indirectly affect the environment and ecology. Therefore, this matter is receiving increasing attention. A typical arid area with a fragile ecological environment and frequent dust activities, Xinjiang, China, was investigated using Moderate Resolution Imaging Spectroradiometer (MODIS) daily aerosol optical thickness and Ångström wavelength exponent data to obtain the temporal and spatial distribution characteristics of long-term dust aerosols over 20 years. The frequency of occurrence was calculated to accurately identify anthropogenic and natural sources, and data, such as wind speed, were superimposed to quantitatively estimate dust aerosol emissions. The factors that influenced dust aerosol emissions are discussed. The results show that the distribution of dust aerosols in South and North Xinjiang is obviously different, and the average dust aerosol optical depth (DOD) in spring is higher than that in other seasons. The sources of natural dust have little variation and are primarily located in Lop Nur, on the edges of the Taklamakan and Gurbantunggut deserts, in the central Tuha Basin, and in dried-up lakes. The sources of anthropogenic dust are mainly distributed in the farmland areas of the oasis plain and the impact fan plain. Natural dust aerosols are dominant in Xinjiang, with high natural dust emissions in spring. Changes in anthropogenic dust aerosols are caused by production activities, and the annual average anthropogenic dust emissions account for 8% of the total dust emissions. Precipitation can promote a reduction in natural dust emissions. Topography has an obvious effect on the formation and transportation of dust aerosols, which manifests as the frequent occurrence of dust in the basin. The population density data and Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light data reveal, that the intensity of human activities has a great impact on anthropogenic dust aerosols. This study provides support for research on how aerosols affect climate and environmental changes in Xinjiang. Highlights: · Daily dust aerosol optical depth (DOD) data was obtained from 2003 to 2019 · Anthropogenic and natural dust sources of Xinjiang, China, were identified · Dust aerosols emissions in dust sources were quantitatively estimated · The influences of precipitation, topography, and human on dust aerosols were analyzed