ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-10-5641-2010 Spatial distribution and interannual variation of surface PM<sub>10</sub> concentrations over eighty-six Chinese cities Qu W. J. 1 2 Arimoto R. 3 4 Zhang X. Y. 2 Zhao C. H. 1 Wang Y. Q. 2 Sheng L. F. 1 Fu G. 1 Physical Oceanography Laboratory, Ocean-Atmosphere Interaction and Climate Laboratory, Department of Marine Meteorology, College of Physical and Environmental Oceanography, Ocean University of China, 238 Songling Rd., Laoshan District, Qingdao 266100, Chi Key Laboratory of Atmospheric Chemistry, Centre for Atmosphere Watch and Services (CAWAS), Chinese Academy of Metrological Sciences, China Meteorological Administration, 46 Zhong-Guan-Cun S. Ave., Beijing 100081, China Carlsbad Environmental Monitoring and Research Center, New Mexico State University, Carlsbad, New Mexico, USA retired 29 06 2010 10 12 5641 5662 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/10/5641/2010/acp-10-5641-2010.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/5641/2010/acp-10-5641-2010.pdf

The spatial distribution of the aerosols over 86 Chinese cities was reconstructed from air pollution index (API) records for summer 2000 to winter 2006. PM<sub>10</sub> (particulate matter ≤10 μm) mass concentrations were calculated for days when PM<sub>10</sub> was the principal pollutant, these accounted for 91.6% of the total 150 428 recorded days. The 83 cities in mid-eastern China (100° E to 130° E) were separated into three latitudinal zones using natural landscape features as boundaries. Areas with high PM<sub>10</sub> level in northern China (127 to 192 μg m<sup>−3</sup>) included Urumchi, Lanzhou-Xining, Weinan-Xi'an, Taiyuan-Datong-Yangquan-Changzhi, Pingdingshan-Kaifeng, Beijing-Tianjin-Shijiazhuang, Jinan, and Shenyang-Anshan-Fushun; in the middle zone, high PM<sub>10</sub> (119–147 μg m<sup>−3</sup>) occurred at Chongqing-Chengdu-Luzhou, Changsha-Wuhan, and Nanjing-Hangzhou; in the southern zone, only four cities (Qujing, Guiyang, Guangzhou and Shaoguan) showed PM<sub>10</sub> concentration >80 μg m<sup>−3</sup>. The median PM<sub>10</sub> concentration decreased from 108 μg m<sup>−3</sup> for the northern cities to 95 μg m<sup>−3</sup> and 55 μg m<sup>−3</sup> for the middle and southern zones, respectively. PM<sub>10</sub> concentration and the APIs both exhibited wintertime maxima, summertime minima, and the second highest values in spring. PM<sub>10</sub>showed evidence for a decreasing trend for the northern cities while in the other zones urban PM<sub>10</sub> levels fluctuated, but showed no obvious change over time. The spatial distribution of PM<sub>10</sub> was compared with the emissions, and the relationship between the surface PM<sub>10</sub> concentration and the aerosol optical depth (AOD) was also discussed.

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