Atmos. Chem. Phys., 18, 8849–8871, 2018 https://doi.org/10.5194/acp-18-8849-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Characteristics of PM2:5 mass concentrations and chemical species in urban and background areas of China: emerging results from the CARE-China network Zirui Liu1, Wenkang Gao1, Yangchun Yu1, Bo Hu1, Jinyuan Xin1, Yang Sun1, Lili Wang1, Gehui Wang3, Xinhui Bi4, Guohua Zhang4, Honghui Xu5, Zhiyuan Cong6, Jun He7, Jingsha Xu7, and Yuesi Wang1,2 1State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China 3State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 4State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 5Zhejiang Meteorology Science Institute, Hangzhou 310017, China 6Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China 7International Doctoral Innovation Centre, The University of Nottingham Ningbo China, Ningbo 315100, China Correspondence: Zirui Liu (
[email protected]) and Yuesi Wang (
[email protected]) Received: 29 December 2017 – Discussion started: 21 February 2018 Revised: 28 May 2018 – Accepted: 11 June 2018 – Published: 22 June 2018 Abstract. The “Campaign on Atmospheric Aerosol Re- modal and unimodal diurnal variation patterns were identi- search” network of China (CARE-China) is a long-term fied at both urban and background sites.