【摘要】 利用最新安装的塔中"80m观测塔梯度探测系统"资料,详细分析了塔中春季晴天近地层80m高度内平均温度、湿度和风速廓线日变化分布特征,得出以下一些结果:(1)温度廓线有夜间辐射型、早上过渡型、白天日射型和傍晚过渡型四种。夜间近地层大气层结稳定,呈逆温特征;最强逆温出现在凌晨06时,此时,80m高度温差为11.1℃。白天,近地层80m内温度递减率在2.7~5.2℃/100m之间,大气一直处于超绝热不稳定状态。(2)湿度廓线有日夜之分。夜间,30m以下比湿随高度增高急剧变小,30m以上比湿随高度增加而增大,大气呈逆湿特征。白天,比湿随时间一直逐渐变小。在近地层30~50m之间有一个厚度约20m的逆湿层,全天都存在。(3)风速廓线也有日夜之分。夜间稳定层结,廓线风速值以比对数关系更快的速度向上递增,曲线弯向风速轴。白天不稳定层结,廓线风速值以比对数关系较慢的速度向上递增,曲线弯向高度轴。只有在10m以下高度,日夜间的风廓线近似遵循对数律关系。更多还原

【Abstract】 Using the latest data that gathered from the 80 m observing tower gradient detecting system in the hinterland of the Taklimakan Desert,the diurnal changing distribution characteristics of mean temperature,humidity and wind velocity profiles in the 80 m layer above the ground on sunshiny day in spring,2006 have been analyzed and some results have leen drawn:(1)There are four kinds of temperature profile: night radiation pattern,morning transition pattern,daytime insolation pattern and evening transition pattern. At night,the atmospheric stratification is stable and appears a temperature inversion characteristic in the surface layer.The strongest inversion is at six o’clock before dawn and the temperature difference inside 80 m surface layer is 11.1 ℃ at that time.The temperature lapse rate within 80 m surface layer is between 2.7 ℃/100 m and 5.2 ℃/100 m,and the atmosphere is in a superadiabatic unstability state all the daytime.(2)Humidity profiles have a division of night profiles and day profiles. At night,specific humidity decreases rapidly with the height increasing below 32 m,but above 32 m humidity is increasing with height rising,and the atmosphere presents a characteristic of moisture inversion.In daytime,the specific humidity is diminishing gradually with time changing.There is a layer of inverse humidity approximately 20 m thick between the height 30 m and 50 m in the surface layer all day.(3)Wind velocity profiles is also divided into day profiles and night profiles.At night,the wind speed value of wind velocity profiles increases at a quicker rate than the logarithm relation and the curves bend to the wind speed axis.In daytime,the wind speed value increases at a slower rate compared to the logarithm relation and the curves bend to the altitude axis.Only below 10 m height,the wind profiles approximately follow the logarithm law relations in daytime and at night.更多还原