《A study of air pollution of city clusters》.pdf

Atmospheric Environment 45 (2011) 3069e3077 Contents lists available at ScienceDirect Atmospheric Environment journal homepage: www.elsevi /locate/atmosenv A study of air pollution of city clusters Huiwang Gao a, Jing Chen a, Bin Wang a, Sai-Chun Tan b, Colin M. Lee c, Xiaohong Yao a, *, Han Yan a, Jinhui Shi a a Laboratory of Marine Environmental Science and Ecology, MOE, Ocean University of China, Qingdao 266100, China b State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China c Southern Ontario Centre for Atmospheric Aerosol Research, University of Toronto, M5S3E5 Toronto, Ontario, Canada a r t i c l e i n f o a b s t r a c t Article history: In this study, the Daily Air Pollution Index (DAPI) of 81 cities in China from June 2004 to June 2007 was Received 2 November 2010 used to study the air pollution of city clusters. The cluster analysis results show that the DAPI of 71 cities Received in revised form in central and eastern China is divided into two regimes, the north regime and the south regime along 25 February 2011 the Qinling Mountain and its eastern extension to Huaihe River. The demarcation line between the two Accepted 2 March 2011 DAPI regimes duplicates the demarcation line of the watersheds of the northern and southern climate regions and the DAPI were statistically negatively correla