Temporal and Spatial Distribution Characteristics of Tropospheric Hcho Column Concentration Based on Tropomi and Its Response to Driving Factors in North China

Long-term industrialization has led to high HCHO concentrations in North China. In this study, we analyzed the spatial and temporal distribution characteristics of tropospheric HCHO VCD and its driving factors in North China from 2019 to 2023 based on the HCHO daily dataset from TROPOMI. The results showed that the spatial distribution trend of tropospheric HCHO VCD in North China remained unchanged in the past 5 years, with the highest in the center, followed by the east and the lowest in the west. Seasonal variations were clearly characterized, with summer being higher than other seasons and spring being the lowest. In addition, the effects of meteorological elements on HCHO VCD were analyzed based on the ERA5 dataset, and the correlation between HCHO VCD and temperature and wind was strong, while the correlation with precipitation and surface solar radiation was low, and the effects were obviously different between the growing and non-growing seasons. Population density is directly proportional to tropospheric HCHO VCD. In this study, a higher-resolution spatial and temporal distribution model of tropospheric HCHO VCD in North China is obtained based on TROPOMI, which effectively characterizes the driving factors of HCHO VCD.