摘要
分析了 2 0 0 0年 4月 6日沙尘暴期间北京近地层气象要素的变化和沙尘期间土壤尘谱分布及其来源。结果表明 ,沙尘暴发生时 ,近地层风速明显增大 ,空气相对湿度迅速减少 ,边界层湍流交换强烈。沙尘暴期间土壤尘浓度高达 390 6 μg·m-3 ,是1 999年春季非沙尘期间土壤尘浓度的 4 0倍以上。其中粗粒子占了大部分 ,粒径大于1 6 μm、8μm和 2 μm的土壤尘浓度分别占总土壤尘浓度的 6 7%、78%和 94 %之高。沙尘暴过后 ,粗粒子的浓度和所占总浓度比重明显下降 ,但仍大大高于非沙尘期间。后向轨迹分析结果表明 ,此次沙尘暴主要来源于蒙古和内蒙古地区 ,并在强烈的西北气流的推动下经过高空长距离输送到达北京。
A dust storm attacked Beijing on April 6, 2000. The variation of meteorological parameters in the boundary and physical chemical properties of this dust events are studied. The results show that the dust storm leads to the distinct and sharp increase of wind speed, decrease of relative humidity, development of turbulence and mixing capability in boundary layer. The total soil mass concentration of dust on April 6 reached 3906μg·m -3 , 40 times as that of the non dust weather days in 1999 spring. Mass concentration of dust with diameter above 16μm, 8μm and 2μm account for 67%, 78% and 94% respectively. Back trajectory analysis shows that this dust storm on April 6, 2000 originated from Mongolia and Inner Mongolia in China, and arrived in Beijing through long-rang transportation via strong northwest wind.
出处
《气象》
CSCD
北大核心
2005年第2期8-11,共4页
Meteorological Monthly
基金
国家自然科学面上基金项目 (40 2 0 5 0 17)
中国科学院"引进国外杰出人才"计划 (全球环境变化 )项目资助。
