[Spatial and Temporal Characteristics of Ozone Formation Sensitivity and Its Influencing Factors in Chengdu-Chongqing Area].

To study the characteristics of ozone formation sensitivity changes in the Chengdu-Chongqing area, the summer ozone formation sensitivity （OFS） was analyzed using satellite observation of the OMI tropospheric column concentration of HCHO and NO₂. Additionally, the effects of meteorological factors, source emissions, and their interactions on OFS were identified with the geodetic detector. The results showed that the summer OFS zoning in the Chengdu-Chongqing area was dominated by a transitional regime, with an area share of 42.42%. Less VOCs-limited regime was observed, which was mainly distributed in the urban areas of Chengdu City and Chongqing Municipality, with an area share of 16.37%. The NO_x-limited regime was mainly located in Ya'an City, Leshan City, Yibin City, Luzhou City, and the eastern part of Chongqing Municipality, with an area share of 41.21%. The area of the VOCs-limited regime gradually decreased from June to August and reached the lowest value in August, accounting for only 3.53%, and the area of the VOCs-limited regime increased significantly in September. Pollutant emissions （CO, PM_2.5, NMVOC, and NO_x） were the main factors affecting summer OFS in the Chengdu-Chongqing area. With the increase in emissions, the FNR gradually decreased, and the OFS tended to be the VOCs-limited regime. SP, T2, and TCW were the three main meteorological factors that affected the change in summer OFS in the Chengdu-Chongqing area. All three factors were negatively correlated with FNR； the larger the values of SP, T2, and TCW, the more easily OFS changed to a VOCs-limited regime. Interactions between factors exacerbated OFS changes and were the main drivers of spatial and temporal variations for summer OFS in the Chengdu-Chongqing area.