Fig. 1: Evolution of meteorological parameters, particle mass concentration, and size-resolved particle number concentrations during haze.
From: A 3D study on the amplification of regional haze and particle growth by local emissions
Time series of a wind direction (WD) and wind speed (WS), b relative humidity (RH) and temperature (T), c ozone (O3) and nitrogen oxides (NOx = NO + NO2), d mass concentrations of non-refractory submicron aerosols (NR-PM1) and mixing layer height (MLH) during a typical NPF event followed by a severe haze episode. The solid lines are the measurements at ground level and dash lines are measurements at 260 m; e and f show the evolution of size-resolved particle number concentrations at 260 m and ground level, respectively. The right panels are the average size distributions of particle number concentrations for three periods, i.e., initiation (September 13 midday–September 14 midday), accumulation (September 14 midday–September 18 midnight), and scavenge (September 18 midnight–September 18 midday) as indicated in d. In addition, the variations in geometric mean diameter (GMD) of regional new formed particles (circle) and urban new formed particles (cross) from log-normal fitting are also shown. g The ratios of size-resolved particle number concentrations between 260 m and ground level.
