Exploring air pollution characteristics from spatio-temporal perspective: A case study of the top 10 urban agglomerations in China

Air pollution has become a global public health risk factor as rapid urbanization advances. To observe the air pollution situation, air monitoring stations have been established in many cities, which record six air pollutants. Previous studies have identified cities exhibiting similar air pollution characteristics by combining principal component analysis (PCA) with cluster analysis (CA). However, spatial and temporal effects were neglected. In this paper, we focus on the combination of GTWPCA and STCA, which fully incorporates spatio-temporal effects. It is then applied to air pollution data from the top 10 urban agglomerations in China during 2016-2021. Key experimental findings include: 1. GTWPCA provides a more detailed interpretation of local variation than PCA. 2. Compared with CA, STCA highlights the coupling effect in the spatial and temporal dimensions. 3. The combi-nation of GTWPCA and STCA captures similar air pollution characteristics from spatio-temporal perspectives, which has the potential to help environmental authorities take further action to control air pollution.

Automated summary

Air pollution has become a global public health risk due to rapid urbanization. Air monitoring stations have been set up in many cities to observe the situation, recording six air pollutants. Previous studies used PCA and CA to identify cities with similar air pollution characteristics, but ignored spatial and temporal effects. This paper focuses on the combination of GTWPCA and STCA, incorporating spatio-temporal effects and analyzing air pollution data from China's top 10 urban agglomerations during 2016-2021. Key findings include a more detailed interpretation of local variation with GTWPCA compared to PCA, the highlighting of coupling effects in spatial and temporal dimensions with STCA, and the potential for environmental authorities to take further action based on the combination of GTWPCA and STCA to control air pollution.