Insights into an Asian dust event sweeping Beijing during April 2006: Particle chemical composition, boundary layer structure, and radiative forcing
Insights into an Asian dust event sweeping Beijing during April 2006: Particle chemical composition, boundary layer structure, and radiative forcing
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DOI：
10.1029/2009jd013391
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发表时间：
2010-09
影响因子：
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通讯作者：
Weijie Wang;T. Cheng;Renjian Zhang;X. Jia;Z. Han;Xiaoling Zhang;Xiaofeng Xu;Deping Li
中科院分区：
文献类型：
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作者：
Weijie Wang;T. Cheng;Renjian Zhang;X. Jia;Z. Han;Xiaoling Zhang;Xiaofeng Xu;Deping Li
[1]2006年4月16日至20日在北京对春季横扫亚洲大陆的一次特大沙尘天气进行了密集观测。北京遭受了大量的矿物粉尘从逆风地区，确定为蒙古和内蒙古的沙漠地区远距离输送。在沙尘暴发生的黄金时段，PM10小时浓度急剧上升，达到1200 μg/m3，对应的最低能见度为3 km。沙尘日气溶胶中主要地壳元素的质量浓度几乎是非沙尘日的两倍。准静止锋对北京地区强沙尘天气的形成有重要贡献，这是由于来自西伯利亚反气旋的北方冷空气团与南方暖空气团等分量汇合的结果。在沙尘暴期间，对流大气边界层以下的东北急流出现在50-65 m、100-160 m和160-260 m的多层高度，最高风速超过14 m s−1。由于冷空气水平平流的影响，逆温通常发生在160-240 m、60-140 m和5-30 m高度。沙尘暴期间北京大气中沙尘含量的增加导致了大气顶部-62.0 W m−2辐射强迫的冷却效应。
[1] Intense measurements on a giant dust event sweeping over the Asian continent during springtime were conducted in Beijing from 16 to 20 April 2006. Beijing suffered from a large amount of mineral dust transported long range from upwind regions, identified as the desert areas of Mongolia and Inner Mongolia. During the prime time of dust event, hourly PM10 concentrations increased drastically to 1200 μg/m3, corresponding to the lowest visibility of 3 km. The mass concentrations of major crustal elements in aerosols during dusty days were nearly double those of nondusty days. The quasistationary front had great contributions to the formation of severe dusty days over Beijing because of an equiponderant confluence of northern cold air masses from a Siberian anticyclone and southern warm air masses. During the dust event, northeast jets below the convective atmosphere boundary layer occurred at multilevel heights of 50–65 m, 100–160 m, and 160–260 m, with the highest wind speed exceeding 14 m s−1. Humidity inversions usually occurred at heights of 160–240 m, 60–140 m, and 5–30 m due to the cold air horizontal advection. The enhancement of dust loadings in the atmosphere of Beijing during the dust event resulted in a cooling effect by –62.0 W m−2 radiative forcing at the top of atmosphere.