摘要
利用中日合作"风送沙尘的形成、输送机制及其对气候与环境影响(ADEC)的研究"项目敦煌站的沙尘粒子数浓度观测资料,估算了2002年4月敦煌地区两次沙尘天气过程中戈壁沙地的起沙率和起沙量,并分析了地面起沙量(质量通量)的尺度分布。在两次强度较弱、持续时间较短的沙尘天气过程期间,戈壁沙地的平均起沙率为1.58×10-8和9.95×10-9kg·m-2·s-1,最大起沙率为2.77×10-8kg·m-2·s-1。地面沙尘释放量的73%以上为d>5.0μm的大粒子。最后讨论了起沙率与摩擦速度的关系。
Using the dust particle concentration data measured by portable dust particle counter,the dust emission rate over the sand surface of Gobi desert in Dunhuang was estimated. Two dust events occurred on April 8 and 13, 2002 were selected. Each event was divided into the dust storm stage (DCI≥0.4) and 2 blowing dust stages (0.4>DCI≥0.2) before and after dust storm stage. For estimating the dust emission rate by use of the dust particle concentration data, we assumed that the vertical flux of dust particles through 2 m high level is equal to that emitted from the surface. The estimated dust emission rate of both cases (April 8 and 13) are as follows: 0.94×10-8 and 1.03×10-8 kg·m-2·s-1 during the blowing dust stage; 1.18×10-8 and 1.89×10-8 kg·m-2·s-1 during dust storm stage; the mean dust emission rate during whole dust event are 1.00×10-8 and 1.58×10-8 kg·m-2·s-1, respectively; and the maximum emission rate on April 13 was 2.77×10-8 kg·m-2·s-1. The relationship between dust emission rate and frictional velocity was analyzed too.
出处
《高原气象》
CSCD
北大核心
2003年第6期545-550,共6页
Plateau Meteorology
基金
中国科学院创新重大方向项目(KZCX2 305)
国家重点基础研究发展规划项目(G2000048703)
中国科学院中日合作项目资助
关键词
沙尘暴
戈壁沙地
起沙率
粒径尺度分布
Dust strom
Gobi desert
Dust emission rate
Partide size distribution
