Atmospheric dust events in Central Asia: Relationship to wind, soil type, and land use

Authors: PI, HUAWEI - Chinese Academy Of Sciences; Sharratt, Brenton; LEI, JIANGQIANG - Chinese Academy Of Sciences

Submitted to: Journal of Geophysical Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2017
Publication Date: 6/27/2017
Citation: Pi, H., Sharratt, B.S., Lei, J. 2017. Atmospheric dust events in Central Asia: Relationship to wind, soil type, and land use. Journal of Geophysical Research. 122:6652-6671. https://doi.org/10.1002/2016JD026314.
DOI: https://doi.org/10.1002/2016JD026314

Interpretive Summary: Xinjiang Province in Northwest China is one of the dustiest places on Earth. Controlling dust events in the region is critical to improving air quality across China as well as along the west coast of the USA. We found the number of dust storms has declined since 1960, likely due to a decrease in wind speed and increase in precipitation with time in the province. Dust storms were most prevalent in deciduous forests, meadows, and orchards characterized by saline or irrigated soils as compared with other land use and soil types. Therefore, the occurrence of dust storms may be reduced by improving better land management practices in forests, meadows, and orchards in the region.

Technical Abstract: Xinjiang Province is one of the most important source regions of atmospheric dust in China. Spatial-temporal characteristics of dust events in the region were investigated by time series analysis of annual dust event frequency and meteorological data collected at 101 stations in Xinjiang Province from 1960 to 2007. Dust event frequency (DEF), blowing dust frequency (BDF), and dust storm frequency (DSF) decreased with time in North, South, and East Xinjiang. Dust concentrations were lower in North than in South Xinjiang and decreased with time in East Xinjiang. Wind significantly influenced the temporal trend in floating dust frequency, BDF, and DSF in South Xinjiang and DSF in North Xinjiang. Precipitation also influenced dust event activity, although it did not play a dominant role. Frequency of dust events was smaller in North (10.9 d y-1) than in South Xinjiang (111.3 d y-1), possibly due to the more humid climate of North Xinjiang. Floating dust is most frequently observed in East and South Xinjiang while blowing dust is most frequently observed in North Xinjiang. The high frequency of floating dust in East and South Xinjiang is likely due to the enclosed terrain that characterizes these regions. Land use and soil type also influenced dust events. Although climate influences frequency of dust events, the occurrence of these events may be reduced most effectively by imposing better land management practices in deciduous forests or orchards characterized by saline soils in respectively North and East Xinjiang and meadows characterized by Guanyu soils in the South Xinjiang.