稳定大气近地面层的风和温度廓线
PROFILES OF WIND AND TEMPERATURE IN THE STABLE STRATIFIED GROUND LAYER
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摘要: 本文不做风和温度廓线相似性假设,使用最小二乘法分析位于粗糙、不均匀地形上北京气象专用塔在稳定条件下的平均风速和温度测量资料。结果表明,在近地面层,从弱稳定到强逆温的较宽的稳定层结范围内,对数加线性规律都是适用的;廓线参数βu和βθ不是常数,它们的数值随大气稳定度而变化。文中给出的经验公式表明:廓线参数随Ri的增大而减少,随L的增大而增大。在临界理查逊数的两侧,廓线参数随Ri的变化遵循不同的规律。文中还表明,廓线相似性假设仅对大气层结稳定度较弱时才是真实的;当稳定度增大时,廓线变成不相似,P值随Ri的增大而增大。Abstract: In this paper, using least square method instead of similarity hypothesis of profiles between wind and temperature, We analyse data of mean wind and temperature obtained from a meteorological tower at Beijing over rough and inhomogeneous terrain in stable stratif ied condition. The results show that the rule of log+lineal is valid and true within the wide limits of the stable stratification from slight stablity to strong inversion and that the prof ile parameters(βu and βθ)are not constants, but vary with atmospheric stratification condition. The experimental formulae shown here indicate that the profile parameters decrease with incresing of Ri and increase with L. The variation of profile parameters with stability in condition Ri>Rict differs from in condition Rict. They also show that the profile similarity between averaging wind and temperature is true only in the slightly stratified stability and fails as increasing the stability. P increases with Ri.