The analysis of aerosol type and vertical distribution characteristics along Huaihe River based on CALIOP satellite measuring

Based on CALIPSO level 2 aerosol profile data and surface meteorological observation data，aerosol extinction feature in haze was statistically analysed along Huaihe River. Using backward trajectory and cluster analysis method, pollution sources were investigated. Then vertical feature mask data(VFM) and ERA Interim data were used to analyse aerosol type, vertical distribution characteristics and typical weather patterns. The results showed that aerosol extinction coefficient along Huaihe River was largest near the ground with extinction coefficient 0.53 and decreased obviously along with high. Local pollution was primary source with contribution ratio of 46%. Furth more, pollution transmission from Yangtze River delta pollution zone and Beijing-tianjin-hebei was very important for the pollution event in Huai River basin. During stagnant synoptic situation, thermal inversion layer caused by warm advection at 850 hPa resulted in local air pollution, which was composed of continental aerosol. Weak upward motion in the surface layer transported pollutants to 0.4~0.8 km, where aerosol concentration was higher than that on the ground. When subtropical anticyclone 5880 isopiestic line location moves northward and westward, Yangtze River delta was controlled by high pressure through whole layer of the atmosphere, which lead to polluted dust aerosol accumulation. Due to downdraft, extinction effect was strongest near surface and decreased with height. In the early stage of cold air south down, cold north-west airstream caused by cold advection at 850 hPa brought Beijing-tianjin-hebei pollution to Huai River basin. Polluted continental aerosol and dust aerosol was main type of pollutants. The transport height of aerosols may be higher than 2 km with maximum transport being 1~2 km.