Large Asian dust layers continuously reached North America in April 2010
Large Asian dust layers continuously reached North America in April 2010
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DOI：
10.5194/acp-11-7333-2011
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发表时间：
2011-07
影响因子：
6.3
通讯作者：
I. Uno;K. Eguchi;K. Yumimoto;Zhaoyan Liu;Y. Hara;N. Sugimoto;A. Shimizu;T. Takemura
中科院分区：
文献类型：
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作者：
I. Uno;K. Eguchi;K. Yumimoto;Zhaoyan Liu;Y. Hara;N. Sugimoto;A. Shimizu;T. Takemura
抽象。美国航天局星载米氏激光雷达系统CALIPSO/CALIOP显示，2010年4月，水平尺度为2，000 - 3，000公里的多个大型亚洲尘埃层到达北美，占据了整个对流层。这种沙尘层输送在以往的研究中未见报道。我们的分析CALIOP数据和全球气溶胶模式的结果表明，频繁的沙尘排放发生在中国西北部，因为强于平均近地面风，强稳定的西风带亚洲沙尘从中国西北部到太平洋中部。在东太平洋出现了一个负压异常，沙尘的主要输送路径在北美上空分裂为两条分支：一条北方路径和一条南方路径。北道沙尘被困和停滞的时间比南道沙尘长，最后在高压系统下消退。沙尘沿着南部的路径到达美国中部。这些复杂的条件导致了北美上空尘埃的多层结构。
Abstract. The NASA space-borne Mie-lidar system CALIPSO/CALIOP revealed that multiple large Asian dust layers with a horizontal scale of 2000–3000 km reached North America, occupying the full troposphere, in April 2010. This kind of dust layer transport has not been reported before. Our analysis of CALIOP data and global aerosol model results revealed that frequent dust emissions occurred in northwestern China because of stronger-than-average near-surface winds, and that strong stable westerly winds carried the Asian dust from northwestern China to the central Pacific Ocean. A negative pressure anomaly was located in the eastern Pacific Ocean, and the main dust transport path was split into two branches: a northern path and a southern path over North America. Northern-path dust was trapped and stagnant for a longer time than southern path dust and finally subsided under a high-pressure system. Dust along the southern path reached the central US. These complex conditions resulted in a multi-layered structure of dust over North America.