PROCESS, CAUSE AND LAND ASSESSMENT OF THE EXTREME WIND-DUST COMPOUND DISASTER IN CHINA IN APRIL 2025

From 10 to 15 April 2025, China experienced a rare persistent extreme wind-dust compound disaster that swept from north to south. Based on observational data, historical disaster records, and situations of various exposed elements, this study analyzed the formation mechanisms and evolution of this extreme event and conducted a rapid assessment of the associated loss and damage. The results indicate that the direct cause of this extreme wind-dust compound disaster was a strong cold vortex system generated in Mongolia, which moved eastward and southward, combined with the amplification effects of topography and urban structures, and the downward transmission of momentum from higher troposphere. The analysis revealed that approximately 697.47 million people were exposed to strong winds, while about 1,374.54 million people were exposed to high concentrations of PM10. The strong winds also caused varying degrees of damage to buildings, transportation networks, agricultural greenhouses, and forests. Based on vulnerability curves for wind-related loss and damage, it was estimated that the number of victims affected by this extreme wind-dust compound disaster ranged from 0.209 to 1.044 million, with casualties between 5 and 13 individuals. The number of damaged buildings was estimated to be between 2115 and 4607, and the area of affected crops was between 229 and 783 km². The direct economic losses could reach as high as RMB 0.076–3.501 billion yuan. This study revealed the causes of this extreme wind-dust compound disaster and quantified the disaster loss and impact, providing new insights for the prevention of associated disasters.