云南大理干湿季近地层湍流特征对比分析  

Comparative Analyses of Turbulence Characteristics in Near-Surface Layer in Dry/Wet Periods at Dali

作　　者：杨智[1,2] 刘劲松[1] 朱以维[1] 董保举[1] 

机构地区：[1]云南省大理市气象局大理国家气候观象台,大理671003 [2]云南省气象局科技减灾处,昆明650034

出　　处：《气象科技》2009年第4期429-433,共5页Meteorological Science and Technology

基　　金：中日JICA合作项目;云南省气象局青年研究基金;云南省气象局短平快项目(D200807)共同资助

摘　　要：利用大理国家气候观象台2007年3月至2008年1月观测资料,采用涡动相关法等计算方法分析了该地区湍流强度、湍流方差、湍流通量等特征量的日变化规律和干湿季变化特征。结果表明:湍流强度干季大于湿季;湍流方差与稳定度满足1/3次方定律,风速方差在稳定条件下比不稳定条件下离散,水平方向比垂直方向离散;湍流通量有明显日变化特征,感热、动量通量干季大于湿季,潜热通量湿季大于干季,干湿季热量交换以潜热为主。Based on the data of the PBL observation system at Dali from March to December 2007, the characteristics of turbulent intensity, turbulent variances and turbulent flux are analyzed by using the eddy correlation method. The results show that the turbulent intensity in the dry period is much higher than that in the wet period. The relation between the normalized variance of 3D winds and z/L satisfies the law of 1/3 fractional power. In the case o{ stable stratification, the relation of the variance to z/L is dispersed in the horizontal direction. Turbulent flux shows obvious diurnal variation. The values of sensible heat flux and momentum flux are larger in the dry period, but the latent heat flux is lager in the wet period. The latent heat flux is greater in both dry and wet periods.

关 键 词：大理 涡动相关法 近地层 湍流特征 

分 类 号：P425.21[天文地球—大气科学及气象学] O359[理学—流体力学]