Characteristics of Aerosol and Effect of Aerosol-Radiation-Feedback in Handan, an Industrialized and Polluted City in China in Haze Episodes

Abstract

In order to investigate the chemical characteristics of aerosol pollution including PM1 and PM2.5 in Handan, the offline sampling campaign was conducted and the concentrations of total water-soluble inorganic ions (TWSI), carbonaceous components (OC and EC) were analyzed. The average concentrations were 88.5 μg/m3 for PM1 and 122 μg/m3 for PM2.5, and the corresponding ratios of PM1 versus PM2.5 on non-pollution, mild-moderate pollution and heavy pollution were 0.67, 0.70 and 0.77, respectively. TWSI and OC accounted for 43.2% and 15.4% in PM1, 41.8% and 16.0% in PM2.5. Secondary components in PM2.5 and PM1 increased with heavy pollution, SNA (SO42−, NO3− and NH4+) was enriched in PM1 but SOC (Secondary Organic Carbon) was more enriched in PM1–2.5. Furthermore, for evaluating the effect of aerosol feedback the WRF-Chem model was applied to identify the aerosol-radiation interaction of aerosol feedback influence on the PM2.5 concentration and various meteorological factors in Handan. The results indicated that the aerosol radiative effects will result in an average 32.62%(36.18 W/m2) decrease in downward short wave flux at ground surface (SWDOWN), an average 17.52% (39.15 m) and 0.16% (0.44 K) decrease in planetary boundary layer height(PBLH) and surface temperature (T2). The wind speed at 10 m (WS) and relative humidity (RH) will be increased by about 4.16%(0.11 m/s) and 1.89% (0.78%), respectively.

Keywords

• PM₁
• PM_2.5
• water soluble inorganic ions
• carbonaceous components
• aerosol feedback