Using composite fingerprints to quantify the potential dust source contributions in northwest China

Area of Science:

• Atmospheric Science
• Environmental Science
• Geochemistry

Background:

• Dust storms significantly impact atmospheric conditions, global climate, and human health.
• Understanding dust storm origins is crucial for research and sustainable development in Northwest China.

Purpose of the Study:

• To identify and quantify the sources of sand and dust storms in Northwest China.
• To differentiate between natural and anthropogenic contributions to dust storms.

Main Methods:

• Analysis of geochemical elements in topsoil and atmospheric dust samples.
• Utilized HYSPLIT backward trajectory model, MODIS satellite imagery, and PM10 monitoring data.
• Applied the composite fingerprints method with an end-member model to trace and quantify sources.

Main Results:

• Key source areas identified: Kumtag Desert, Hexi area, and Inner Mongolia's Gobi Desert.
• Natural sources generally contributed more than anthropogenic ones, especially in Alxa League.
• Anthropogenic sources accounted for ~40% in urban areas, with agriculture being a major source in Zhangye City.
• Source contributions decreased from west to east due to distance; sources were more widespread in the east due to westerly winds.
• Badain Jaran and Tengger Deserts were not major sources due to sand control and desert composition.

Conclusions:

• The study successfully traced and quantified dust storm sources in Northwest China.
• Both natural and anthropogenic factors significantly contribute to dust storms, highlighting the need for integrated management strategies.
• Findings are vital for sustainable development and mitigating the adverse effects of dust storms in the region.