[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 NO. 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-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, NMVOC, and NO） 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.