高级检索

    塔里木盆地东部地区一次典型区域性沙尘天气分析

    Analysis of a typical regional sand-dust event over the eastern Tarim Basin

    • 摘要: 利用地面气象观测资料、探空观测和美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)资料,对塔里木盆地东缘的一次典型区域性沙尘天气过程进行分析,并探讨其滞空原因及传输特征。结果表明:南疆盆地热低压的强烈发展及气温异常偏高为沙尘天气的发生提供了动力和热力条件;在浮尘天气维持期间,塔里木盆地近地层层结较稳定,垂直湍流较弱,逆温层温差与能见度具有较好的对应关系,逆温层厚度较稳定;强沙尘天气期间,逆温层中温度梯度明显,接地逆温层厚度越薄,浮尘物越易出现沉降现象,能见度则出现好转;沙尘暴转为浮尘天气时,逆温层温差和厚度存在明显的跃增;当质点移动路径经过库尔勒地区的西南或东南方向的两个关键区时,可能对库尔勒地区的沙尘天气造成影响,当质点移动以偏东路径为主时,将有利于库尔勒地区的浮尘减弱;由于受若羌地区的地理环境影响,东北、西南或偏西路径均可以造成若羌地区出现沙尘天气。

       

      Abstract: A typical regional sand-dust weather event over the eastern margin of the Tarim Basin was analyzed and the reason of dust hover and transport characteristics were also explored using the surface meteorological data,sounding observations,and National Centers for Environmental Prediction (NCEP) reanalysis data.The results showed that the intense development of a thermal depression in the southern Xinjiang Basin and abnormal high temperature provide dynamic and thermodynamic conditions for the occurrence of sand-dust event.During the maintenance of floating dusty weather,the near-surface layer in the Tarim Basin is characterized by stable stratification and weak vertical turbulence.The temperature difference of the inversion layer has a good correspondence with visibility,and the thickness of the inversion layer varied little.During the strong sand-dust weather,the temperature gradient in the inversion layer increases and the subsidence of floating dust particles occurs as the thickness of surface inversion layer becomes thinner,which leads to a higher visibility.When the dust storm turns to floating dusty weather,the temperature difference and thickness of the inversion layer increases significantly.When the dust storm moving path passes through two key regions including the southwest and the southeast regions of Korla,it probably affects the dust weather over the Korla region,while the particles moving along the eastern path will reduce the floating dust over the Korla region.Due to the effect of the geographical environment of Ruoqiang area,the northeast,southwest,or west paths can cause sand-dust weather over the Ruoqiang area.

       

    /

    返回文章
    返回