塔克拉玛干沙漠腹地沙尘暴过境时近地层风速、温度和湿度廓线特征

Profile Characteristics of Wind Velocity, Temperature and Humidity in the Surface Layer during a Sandstorm Passing Taklimakan Desert Hinterland

利用塔中80m梯度观测塔探测系统采集的资料,详细的分析了2006年4月10日沙尘暴过境时,塔克拉玛干沙漠腹地近地层风速、温度和湿度廓线的演变特征。结果表明:风速廓线满足风速值随高度增高而增大,风速梯度随高度增高而减小的对数律关系;沙尘暴由爆发前到过境时,温度廓线的温度值由随高度增高而增大转变为温度值随高度增高而减小,同时在贴地层2m处存在一微弱拐点;沙尘暴过境时,近地层大气出现微弱逆湿现象,并在不同高度上存在多处拐点,比湿增减在时间上与风速的增减呈负相关性,且整个沙尘暴天气是一个降温增湿的过程。

Using the latest data which gathered from the meteorological gradient tower by the height 80m in the hinterland of Taklimakan Desert, we detailedly analyzed the evolution characteristics of wind velocity, temperature and humidity profiles in the surface layer during a sandstorm passing Taklimakan Desert hinterland on April 10, 2006.The results indicated： the wind velocity profiles satisfied logarithmic rule that the wind speed value increased and the wind speed gradient decreased with increasing height; during the sandstorm erupted and passed, the temperature value of profiles changed from increasing to decreasing with height increasing, and simultaneously, a weakinflection point existed at the height of 2 m near the ground; when this sandstorm was passing, the phenomena of weak inverse humidity appeared in the atmospheric surface layer and there were many inflection points at different height, the fluctuation between the specific humidity and the wind speed assumed negative correlation along with the time. The weather of sandstorm is a process which temperature decreases and humidity increases.