Long-term reconstruction of NO2 photolysis rate coefficients using machine learning and its impact on secondary pollution: A case study in a megacity of the Sichuan Basin, China
Tong Li , Song Liu , Dongyang Chen , Ruirui Zhang , Hefan Liu , Danlin Song , Qinwen Tan , Hongbin Jiang , Li Zhou , Fumo Yang
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引用次数: 0
Abstract
The NO2 photolysis rate coefficient (JNO2) is a critical parameter for assessing the intensity of atmospheric photochemical reactions. However, continuous long-term measurements of JNO2 are scarce. In this study, we developed a machine learning-based method to reconstruct hourly JNO2 values, applying it to a megacity in the Sichuan Basin from 2015 to 2023. The model exhibited strong performance with cross-validation R2 = 0.854 and RMSE = 8.15 × 10−4 s−1. Utilizing the Shapley Additive Explanations (SHAP) method, we identified solar activity and pollutant levels both as significant predictors for JNO2. Our long-term JNO2 reconstructions indicate a strong correlation between JNO2 and ozone concentration, highlighting its important role in secondary pollution. This study illustrates the effectiveness of machine learning in reconstructing hourly JNO2 values, providing a valuable enhancement to traditional models. The findings are crucial for understanding regional photochemical processes and for analyzing trends and causes of ozone and aerosol pollution.
期刊介绍:
Atmospheric Pollution Research (APR) is an international journal designed for the publication of articles on air pollution. Papers should present novel experimental results, theory and modeling of air pollution on local, regional, or global scales. Areas covered are research on inorganic, organic, and persistent organic air pollutants, air quality monitoring, air quality management, atmospheric dispersion and transport, air-surface (soil, water, and vegetation) exchange of pollutants, dry and wet deposition, indoor air quality, exposure assessment, health effects, satellite measurements, natural emissions, atmospheric chemistry, greenhouse gases, and effects on climate change.