Particulate air pollution in Lanzhou China

Concentrations of total suspended particles (TSP) and PM 10 in Lanzhou China have been kept high for the past two decades. Data collected during the intensive observational period from October 1999 to April 2001 show high TSP and PM 10 concentrations. Starting from November, the PM 10 pollution intensifies, and reaches mid to high alert level of air pollution, continues until April next year, and is at low alert level in the summer. In the winter and spring, the TSP concentration is 2–10 times higher than the third-level criterion of air quality (severe pollution). Effects of intrinsic factors (sources of pollution) and remote preconditions (propagation of dust storms) for severe PM 10 and TSP pollution in Lanzhou are analyzed.