Estimation of Short-Term and Long-Term Ozone Exposure Levels in Beijing–Tianjin–Hebei Region Based on Geographically Weighted Regression Model.

In recent years, ozone (O₃) concentration has shown a decreasing trend in the Beijing–Tianjin–Hebei (BTH) region in China. However, O₃ pollution remains a prominent problem. Accurate estimation of O₃ exposure levels can provide support for epidemiological studies. A total of 13 variables were combined to estimate short- and long-term O₃ exposure levels using the geographically weighted regression (GWR) model in the BTH region with a spatial resolution of 1 × 1 km from 2017 to 2020. Five variables were left in the GWR model. O₃ concentration was positively correlated with temperature, wind speed, and SO₂, whereas is was negatively correlated with precipitation and NO₂. Results showed that the model performed well. Leave-one-out cross-validation (LOOCV) R² for short- and long-term simulation results were 0.91 and 0.71, and the values for RMSE were 11.14 and 3.49 μg/m³, respectively. The annual maximum 8 h average O₃ concentration was the highest in 2018 and the lowest in 2020. Decreasing concentrations of major precursors of O₃ due to the regional joint prevention and control may be the reason. O₃ concentration was high in the southeast of the BTH region, including in Hengshui, Handan, Xingtai and Cangzhou. [ABSTRACT FROM AUTHOR]