Spatial and temporal variability of air quality in Shanghai in 2015 Li Liu, Lihuan He, Yu Bai, Mi Zhou, Fengying Zhang, Yirui Wu, Guowei Gao and Yang Yu E3S Web Conf., 194 (2020) 05063 Published online: 15 October 2020 DOI: 10.1051/e3sconf/202019405063