Aircraft Measurements of the Aerosol Spatial Distribution and Relation with Clouds over Eastern China

To investigate the spectral and spatial distribution characteristics of aerosol particles over eastern China, this study conducted a set of aircraft measurements during August 12-28, 2014, over Anhui province, China. The aerosol number concentration and size distributions from five flights as well as the cloud and meteorological parameters were analyzed. In Anhui province, the average number concentration of aerosol particles in the size range of 0.1-3.0 μm was 481 ± 199 cm^(-3), and accumulation mode particles accounted for more than 95% of the total aerosol particles. Most of the aerosol particles were concentrated in the layer below 1000 m, where the number concentration decreased with the altitude, except in the presence of thermal inversion layers (TILs). The TILs prevented the vertical transport of aerosol particles, and led to a higher number concentration in the boundary layer. A large fraction of aerosol particles was removed when clouds were present, and the removed in-cloud aerosols lead to an increase in cloud droplet concentrations for the size range of 3.5-10.0 μm. Our results are valuable for understanding the spatial distribution of aerosol particles and their interactions with clouds.