摘要
动量下传对沙尘暴的发生发展起着十分重要的作用。选取2002年3月18—22日发生在我国华北地区的一次强沙尘暴过程,利用中尺度气象模式MM5V3.7输出的高分辨率动力协调资料,应用位涡理论详细探讨了沙尘暴发生发展的动量下传过程。结果表明:①蒙古气旋是此次强沙尘暴的主要影响系统;大风与干燥低湿是风蚀起沙的前提条件。②沙尘暴过程中,位涡沿等熵面下滑是高、低层动量交换的重要环节,揭示了沙尘暴动量下传的物理机制。
The mesoscale meteorological model （MM5V3.7） is used to simulate a strong sand and dust storm （SDS） process in North China from 18 to 22 March 2002. With the high-resolution data from MM5V3.7, the PV-theory （potential vortieity） is applied to reveal the mechanism of downward momentum transport. The results show that： （1） the Mongolia cyclone was the main weather system during this strong SDS process, and gales and dryness were the preconditions of the wind erosion; （2） the downward transportation of potential vorticity along the iso-entropy surface was the most important process during the SDS, which clearly reveals the mechanism of downward momentum transport.
出处
《气象科技》
2012年第5期820-826,共7页
Meteorological Science and Technology
关键词
强沙尘暴
动量下传
诊断分析
位涡
strong sandstorm
momentum transmission
diagnose analysis
potential vorticity
