The Analysis of Physical Feature of Aerosol Particles in Autumn over Shijiazhuang Area

Based on the arosol data observated by aircraft in convective baundary layer(at altitudes below 4000m above the ground) under different weather conditions during autumn in 1990 over shijiazhuang area, the daily change of number density of aerosol particles and quality concentration in horizontal and vertical derection are analyzed.The results show that the aerosol particles are of local ones under clear air over Shijiazhuang area. The concentration of aerosol particles is from 0. 15 ×10^-9 to 0. 85 ×10^-9g. cm^-3.The characteristic value of spectral distribution N₀ is from 1.5×10⁵ to 5.5×10⁵g. cm^-3，and l value is from 13 to 15 µm^-1 below 4000 meters.The upward transport of aerosol particles is limited，and its distribution occurred discontinuity due to the inversion layer.

The daily change of aerosol number density in the morning was greater than that in the afternoon,but the particle spectra broadened in the afternoon.The spectral distrbution of aerosol particles was affeeted for the city effeet.The number density of aerosol partieles over the city area was 15% -30% higher than that over the rural areas.

Key Words:aerosol particle, number density ,quality concentration ,distribution character

Acknowledgments： This research was supported by National Public Benefit Research Foundation Contact GYHY200806001, GYHY200706036, Key Laboratory for Cloud Physics and Weather Modification of CMA Contract 2009Z0034 and Science Research Contact 09KY11.