Particulate Matter Pollution and Population Exposure Assessment over Mainland China in 2010 with Remote Sensing

The public is increasingly concerned about particulate matter pollution caused by respirable suspended particles (PM(10)) and fine particles (PM(2.5)). In this paper, PM(10) and PM(2.5) concentration are estimated with remote sensing and individual air quality indexes of PM(10) and PM(2.5) (IPM(10) and IPM(2.5)) over mainland China in 2010 are calculated. We find that China suffered more serious PM(2.5) than PM(10) pollution in 2010, and they presented a spatial differentiation. Consequently, a particulate-based air quality index (PAQI) based on a weighting method is proposed to provide a more objective assessment of the particulate pollution. The study demonstrates that, in 2010, most of mainland China faced a lightly polluted situation in PAQI case; there were three areas obviously under moderate pollution (Hubei, Sichuan-Chongqing border region and Ningxia-Inner Mongolia border region). Simultaneously, two indicators are calculated with the combination of population density gridded data to reveal Chinese population exposure to PM(2.5). Comparing per capita PM(2.5) concentration with population-weighted PM(2.5) concentration, the former shows that the high-level regions are distributed in Guangdong, Shanghai, and Tianjin, while the latter are in Hebei, Chongqing, and Shandong. By comparison, the results demonstrate that population-weighted PM(2.5) concentration is more in line with the actual situation.