Based on a bimodal normal distribution for dust size distribution, a quantitative method for estimating dust input was established in this study, and then the transport, microphysics, and environmental effects of a dust event from 26 to 28 November 2025 were investigated based on a multi-source vertical remote sensing system in Zhejiang. The results indicate that the net PM10 input was approximately 7760 tons, exhibiting a spatial distribution that decreased from northeast to southwest. The net input per unit area ranged from 0.001 to 0.293 t/km2. The dust was coarse-dominated, initially lowering the PM2.5/PM10 ratio, which later recovered due to gravitational settling and aging. A distinct “upper-small, lower-large” depolarization ratio profile, caused by gravitational settling and hygroscopic absorption, signaled dust intrusion into the breathing zone and an imminent rise in surface PM10, thereby providing a potential early-warning indicator. Dust influx first elevated the relative humidity below the dust layer via radiative cooling but later reduced the near-surface humidity through hygroscopic absorption after settlement. Additionally, decreases in SO2 and NO2 suggested a potential mitigation of atmospheric acidity by the dust. The O3 response showed spatial heterogeneity: in most areas, it was negatively correlated with NO2, reflecting NO2 titration effects under a VOC-controlled regime, while, in a few areas, both decreased synchronously. These findings underscore the dual physical–chemical impacts of dust on regional air quality and support the development of dust-related pollution early-warning systems.
毛敏娟 et al. (2026) studied this question.