Strong Ozone Intrusions Associated with Super Dust Storms in East Asia

As one of the largest dust source regions, China suffers from frequent dust storms in spring. During the super dust storm in March 2021, a rapid increase in nocturnal surface ozone concentration was observed along with elevated dust loading. Ground-based and satellite observations as well as reanalysis data of air quality and meteorology are integrated to shed light on the ozone anomaly. It is indicated that cold fronts and cyclones are conducive to both dust emissions and the downwards transport of stratospheric air, leading to simultaneously soaring ozone and particle concentrations near the surface. Statistically, in the past few years, under the influence of specific synoptic weather accompanied with Stratosphere-Troposphere Exchange (STE), dust was frequently uplifted to 8-12 km and the low-tropospheric ozone was elevated by approximately 6 ppb in northern China during spring dust storms. This work reveals strong ozone intrusions associated with dust storms, which have great impacts on atmospheric chemistry and regional climate.