Interactions between Meteorological Conditions and Surface Ozone in Urban, Industrial, and Rural Environments

Ozone has emerged as a critical air quality challenge in many regions, with its formation and accumulation controlled not only by precursor emissions but also by meteorological conditions and boundary-layer dynamics. This study investigates ozone pollution across three representative regional types: a densely populated urban area, an industrial-port region, and a rural background site characterized by relatively limited anthropogenic emissions. The aim is to elucidate the dominant controlling processes under different emission and meteorological regimes. Long-term air quality observations were combined with UAV-based vertical measurements and backward trajectory analysis to characterize the spatiotemporal variability of ozone across these regional settings. Long-term trend analyses reveal pronounced seasonal variability in surface ozone levels across all three regions, with no evident long-term decreasing trend, despite overall reductions in ozone precursor emissions. In contrast, PM_2.5 concentrations show a consistent decline, highlighting differences in the governing mechanisms of gaseous and particulate air pollutants. Precursor concentrations remain notably higher in the industrial–port region compared with urban and rural areas, reflecting the influence of emission structure on ozone formation potential. Correlation analyses show generally weak to moderate relationships between surface ozone and meteorological variables, with weak winds and synoptic-scale atmospheric stability favoring ozone accumulation. UAV-based vertical observations further reveal frequent nighttime formation of stable boundary layers and elevated residual ozone layers across seasons, suggesting that vertical carryover processes play an important role in modulating next-day surface ozone. Backward trajectory analyses demonstrate that high-ozone episodes are primarily associated with regional stagnation and short-range transport rather than long-range transport. Overall, this study highlights the critical role of boundary-layer dynamics, vertical ozone structures, and regional meteorological conditions in influencing ozone pollution across various regional typologies. These findings provide transferable insights for the development of effective ozone mitigation strategies and air quality management in coastal and industrialized regions.