Physical characteristics of dust aerosol over Hunshan Dake sandland in Northern China

Physical characteristics of dust aerosol were determined for samples collected from Hunshan Dake sandland of China in spring 2001. Number concentration and size distributions of particles with 0.5<D-p<100.0 mum were examined. During the field periods the average number concentration of aerosols was 1078.9 cm(-3) on heavy dusty days and 31.4 cm(-3) on non-dusty days. The maximum of aerosol number concentration was 5776.2 cm(-3). The particles with D-p < 8.0 mum accounted for over 90% of total aerosol number loading. With aerosol number concentration increasing the ratio of super-micron particles to total particles in per unit cubic volume gradually rose, but the ratio of sub-micron particles to total particles reduced. The particle size distributions of aerosols were characterized by bi-modal logarithm normal function in heavy and moderately dusty days, and mono-modal in windblown and non-dusty days. (C) 2004 Elsevier Ltd. All rights reserved.