强沙尘暴过程高空温湿风结构和大气稳定度分析  

Analysis on the Upper-air Temperature,Humidity,Wind Speed and Heat Stability during a Sandstorm

作　　者：田庆明[1,2,3] 马廷德 刘晓云 岳平[1,3] 

机构地区：[1]中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室,中国气象局干旱气候变化与减灾重点开放实验室,甘肃兰州730020 [2]酒泉市气象局,甘肃酒泉735000 [3]张掖国家气候观象台,甘肃张掖734000

出　　处：《干旱区研究》2008年第5期700-704,共5页Arid Zone Research

基　　金：国家自然科学基金项目(40765005);中国气象局干旱气象基金(AM200817)共同资助

摘　　要：利用2004年5月23～24日沙尘暴过程中民勤站观测资料，分析了湿饱和位温、比湿和风速垂直廓线分布特征及沙尘暴期间沙尘暴强度、地面气象要素和螺旋度之间的对应关系。结果显示：在沙尘暴爆发前，大气层结处于不稳定状态，大气温、湿风垂直结构有利于沙尘暴的发生发展；沙尘暴期间，大气稳定度逐渐增大，出现了稳定与不稳定相间的情况，不利于对流的进一步发展；特别是在沙尘暴生命史后期阶段，大气层结调整到稳定状态，抑制了干对流的发展。在沙尘暴过程中，螺旋度与地面气象要素及沙尘暴强度之间存在很好的对应关系。Affected by severe invasion of cold air current, a severe sandstorm occurred in Minqin County located in the Hexi Corridor of Gansu Province during the period from May 23 to 24, 2004, the duration of strong wind with wind speed ≥ 12 m/s was as long as 5 hours, and the minimum horizontal visibility was 200 m only. In this paper, the vertical profiles of saturation potential temperature, specific humidity and the wind speed during the sandstorm are analyzed using the radar-sounding data measured by Minqin Meteorological Station during the sandstorm. Moreover, the correlations between the sandstorm intensity and the meteorological factors and RSH values are also analyzed. The results show that the atmosphere stratification was unstable and the vertical structure of air temperature, humidity and wind speed was advantageous for the occurrence and development of the sandstorm before the sandstorm occurred. During the sandstorm, the atmospheric stability was gradually increased, and the atmospheric stability and instability occurred alternately, which was disadvantageous for the further development of sandstorm. Especially, the development of dry convection was restricted after the atmospheric structure became stable at the end of the sandstorm. The study results reveal that there are some good correlations between the sandstorm intensity and the meteorological factors and RSH values.

关 键 词：沙尘暴 气象要素 稳定度 民勤 

分 类 号：P445.4[天文地球—大气科学及气象学]