Acta Scientiarum Naturalium Universitatis Pekinensis

Previous Articles     Next Articles

The Characteristics of Dissipation Rates of Turbulent Variance over Damxung Area in the TIbetan Plateau

LI Fuyu1, ZHANG Hongsheng1, 4, LI Shiming2, ZHOU Mingyu2, CHEN Jiayi1, XU Xiangde3, LIU Huizhi4, HU Fei4   

  1. 1Department of Atmospheric Sciences, School of Physics, Peking University, Key Laboratory of the Rain Storm, Drought and Waterlog of Ministry of Education, Beijing,100871;2The National Center of Marine Environmental Forecast, Beijing,100081;3Chinese Academy of Meteorological Sciences,Beijing,100081;4Chinese Academy of Sciences, Institute of Atmospheric Physics, Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Beijing, 100029
  • Received:2003-06-05 Online:2004-09-20 Published:2004-09-20

青藏高原当雄地区湍流脉动耗散率特征研究

李富余1,张宏升1,4,李诗明2,周明煜2,陈家宜1,徐祥德3,刘辉志4,胡非4   

  1. 1北京大学物理学院大气科学系暴雨与旱涝灾害教育部重点实验室,北京,100871:2国家海洋环境预报中心,北京,100081;3中国气象科学研究院,北京,100081;4中国科学院大气物理研究所大气边界层和大气化学国家重点实验室,北京,100029

Abstract: The turbulent data obtained from Damxung site during TIPEX in 1998 were used to study the characteristics of dissipation rates of turbulent kinetic energy, temperature variance and humidity variance in the middle area of Tibetan Plateau. The results indicate that the dimensionless dissipation rates of turbulent energy are 20% less than the energy produced by velocity shear, and the dimensionless temperature and humidity variances are also 20% less than the variances produced by temperature and humidity gradients. These deficits appear to increase with the increasing of the absolute stability parameter. Moreover, the effects of turbulent transportation and pressure variance, which are related with the stability parameter, persist throughout the whole stability region. The differences between these results and some previous studies show the underlying-surface-dependant characteristics of the dissipation rates of turbulent energy, temperature variance and humidity variance.

Key words: dissipation rate, turbulent kinetic energy, temperature variance, humidity variance, observational method

摘要: 利用1998年第2次青藏高原气象科学实验(TIPEX)当雄地区观测站的湍流资料,分析了青藏高原中部地区湍流动能、温度脉动和湿度脉动耗散率的特征规律。结果表明,无量纲湍能耗散率φε、无量纲温度脉动耗散率φN和无量纲湿度脉动耗散率φγ分别比风速梯度产生的能量、温度和湿度梯度产生的脉动约小20%,且随稳定度参数的绝对值的增加而呈增加的趋势;湍流输送和压力脉动项的影响贯穿于整个稳定度区间, 数值与z/L相联系。青藏高原中部地区湍流动能、温度脉动和湿度脉动耗散率的方程中系数与前人结果的差异,反映其对下垫面特征的依赖性。

关键词: 耗散率, 湍流动能, 温度脉动, 湿度脉动, 观测法

CLC Number: