Research Progress on the Spatiotemporal Variation of Ozone Pollution and Influence of Stratospheric Intrusion in Sichuan Basin

The Sichuan Basin (SCB), adjacent to the east of the Tibetan Plateau (TP), is one of the key regions of air pollution in China. With the thermal and dynamic forcing of the large-scale TP topography, the SCB exhibits unique air pollution characteristics. As a major air pollutant in the environmental atmosphere, tropospheric ozone (O₃) poses a serious threat to human health and natural environment from the tropospheric photochemical reactions and stratospheric intrusion (SI). Previous studies have mainly focused on the impacts of anthropogenic emissions and meteorological conditions on the photochemical O₃ formation, but scarcely on the influence of SI on near-surface O₃ pollution. Therefore, this paper reviews a series of related studies including: (1) The spatiotemporal variations of near-surface O₃ pollution in the SCB and its sources. (2) The influence of the large-scale TP-SCB topography on O₃ pollution changes over the SCB, especially the modulation of thermal and dynamic forcing of the large-scale topography. (3) The influence of SI on the atmospheric environmental changes over the SCB and the multi-scale atmospheric circulation coupling driving mechanism of stratospheric O₃ cross-layer transport under the unique plateau-basin topographic forcing. These studies enhance the comprehensive scientific understanding of the spatiotemporal variations in O₃ pollution over the SCB, the impacts of SI on SCB’s near-surface atmosphere, and their interaction mechanisms with the deep basin terrain, which can be applied in effective O₃ pollution control strategies.