Fig. 1: Evolution of meteorological parameters and particle mass concentration during the haze event.

Time series of a mass concentrations of fine particulate matter (PM_2.5, green line) and visibility (orange line), b temperature (red line) and relative humidity (blue line), c wind speed (black line) and wind direction (dark blue circle) during the haze event from January 14th to January 28th, 2015. The blue rectangle represents clean period and the gray rectangle represents haze period.