Understanding the Rising Phase of the PM_2.5 Concentration Evolution in Large China Cities.

ABSTRACT: Long-term air quality observations are seldom analyzed from a dynamic view. This study analyzed fine particulate matter (PM_2.5) pollution processes using long-term PM_2.5 observations in three Chinese cities. Pollution processes were defined as linearly growing PM_2.5 concentrations following the criteria of coefficient of determination R² > 0.8 and duration time T ≥ 18 hrs. The linear slopes quantitatively measured pollution levels by PM_2.5 concentrations rising rates (PMRR, μg/(m³·hr)). The 741, 210 and 193 pollution processes were filtered out, respectively, in Beijing (BJ), Shanghai (SH), and Guangzhou (GZ). Then the relationships between PMRR and wind speed, wind direction, 24-hr backward points, gaseous pollutants (CO, N

SUBMITTER: Lv B 

PROVIDER: S-EPMC5404509 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature