Characteristics of 0.010-10 µm dust aerosol distribution in dusty weather in semiarid areas.

Using a WPS particle spectrometer,this study observed the concentration of 0.010-10 μm aerosols in different weather conditions in spring in Zhurihe,Inner Mongolia,and researched the concentration and spectral distribution characteristics of sand dust aerosols under different weather backgrounds.The research results show that dust aerosol number concentrations of 0.010-0.020,0.021-0.100 0.101-1.000 and 1.001-2.500 μm particles are largely different in dusty weather and in the background weather,especially for aerosols with diameter larger than 1.0 μm.The mean concentration of 1.001-2.500 μm aerosols in dusty weather is 35 times that of the background weather.In addition,the daily change characteristics of 0.010-0.020,0.021-0.100,0.101-1.000 and 1.001-2.500 μm particles have larger varieties under different weather conditions.Meteorological factors have obvious effects on the daily distribution characteristics of dust aerosols.At the same time,the dust aerosol size distribution in background and dusty weather was analyzed.It was discovered through spectral pattern fitting of the number concentration of sand dust aerosol that the distributions within 1 h before and after a sandstorm in two different weather backgrounds accord with a Lorentz distribution. The peak of sand dust aerosol distribution 1 h before a sandstorm in dusty weather is an order of magnitude higher than that in the background weather,and the peak radius 1 h after a sandstorm shifts obviously to bigger particles.