A STUDY OF MICROWAVE RADIATION TRANSFER CHARACTERISTICS IN STRATIFIED PRECIPITATION CLOUDS BY COMBINING STRATIFIED CLOUD MODEL WITH MICROWAVE RADIATION TRANSFER MODEL

In this paper,the effect of precipitation particles on microwave radiation transfer characteristics in stratified clouds over the ocean is studied by combining stratified cloud model with microwave radiation transfer model.By comparing the calculated results with the true data,it is found that precipitation particle distribution and water shell around ice phase particle strongly affect the upwelling radiation.Therefore,the precipitation particle distribution and water shellaround ice phase particle must be considered when a calculating scheme is designed for retrieving precipitation in stratified clouds by the use of microwave radiation transfer model.     

THE CHARACTERISTICS OF TURBULENT TRANSPORT IN THE SURFACE LAYER OVER EASTERN TIBET DURING SUMMER 1986

The turbulent fluxes for sensible and latent heat and momentum are computed and analyses are carried outabout the factors in terms of the fluxes,with the profile methods,based on the data from the Tibetan(Xi-zang)Plateau Meteorological Experiment in 1986(TIPMEX-86).It is shown that the fluxes of various kindshave evident diurnal variation,and each decade mean diurnal variation is quite different from others.Thesensible heat flux is about 2/3 less in July than in June.The results indicate that the averaged drag coefficient,C_d,and the averaged bulk transfer coefficient of sensible heat,C_h,are 0.0052 and 0.0075 respectively,for theperiod 13 to 28 in June for Nagqu.But for Lhasa,the mean C_d is 0.0056,and the mean C_h is 0.0085,for the period of June 11 to July 20.It is found that C_d and C_h are not only the function of wind velocity,but also influenced by stability conditions and wind and temperature gradients.     

利用多模传输理论求解块状云的辐射特征

实际云层在水平与垂直方向都是不均匀的,但为了便于计算,绝大多数关于云辐射的理论模式,都采用平面平行模式.到目前为止,解决三维空间辐射传输问题的方法仍然不多.一般采用统计方法和二流近似法,但这两种方法分别在计算机时和计算精度上受到限制.作者在三维多模传输理论与辐射传输计算程序软件包--DISORT的基础上,发展出计算三维孤立云块多次散射过程的一套程序(MM-DISORT),并由此初步探讨了云块的三维立体结构对云的短波吸收的影响.     

移极旋转坐标系中的大气动力学方程

本文仅研究无粘、无地形和绝热运动假定下的大气动力学问题，用分析力学的方法求得了固定在地球上的移极旋转坐标系， 如直角坐标系， 球坐标系和柱坐标系中的第二类 Lagrange方程。从而求得普遍的大气动力学方程。所谓的视示力 —— Coriolis力和离心力 —— 与其它各种力统一处理。当地球自转轴不为坐标系的z轴时，不存在大气运动的对称和反对称性。特别值得提出的是以往很多学者利用柱坐标系来数值模拟台风(飓风)的轴对称和非轴对称性时所使用的基本方程是含糊的， 本文给出了准确的基本方程。     

Measurements Of Turbulence Transfer In The Near-Surface Layer Over The Southeastern Tibetan Plateau

Turbulent flux measurements at Qamdo site over the Tibetan Plateau during TIPEX from May 18 to June 30, 1998 are presented. Sensible heat dominated,accounting for about 66% of the available energy (the sum of net radiation and soil heat flux) prior to the monsoon(dry period), reducing to about 31%, with latent heat increased to about 56% of available energy,in the monsoon season (wet period). Surface energy budget closure on average was about 0.80 (0.85)prior to the monsoon and 0.89 (0.76) during the monsoon using eddy correlation (profile) methods. The sum of latent and sensible heat fluxes calculated from the flux-profilemethod was smaller by about 15% than that from eddy correlation. Martano's method is used toestimate the surface aerodynamic roughness length z₀ and zero plane displacement d from singlelevel sonic anemometer data, giving d = 0.12 m and z₀ = 0.08 m. The overall neutral dragcoefficient (C_DN) and scalar coefficient (C_HN) were found to be C_DN = 0.0055and C_HN = 0.0059 in the southeastern area of Tibet. Their variations with the mean wind speed at 10 m are discussed.     

一类常微分方程组边值问题的求解方法

证明了一类非线性二阶常微分方程组边值问题在一定条件下存在唯一的解并且给出了解的求法。     

青藏高原不同地区夏季近地层能量输送与微气象特征比较分析

利用2009年7月在青藏高原理塘、林芝、海北、拉萨获得的气象观测资料,对比分析了这些地区近地层气象要素、辐射收支及湍流通量日变化特征。结果表明：无论是高原东部、中部还是北部,无论是高原台地还是高山峡谷区,7月份近地层各气象要素、湍流通量、辐射收支都有明显的日变化。各地区的地表辐射、感热、潜热等最高值都出现在中午,最低值出现在早晨。地表反照率日变化均呈早晚高中午低的＂U＂型分布。地面热源强度在白天均为热源,正午为强热源,在夜间表现为弱的冷、热源交替出现。7月份近地层地气热量交换中,感热输送作用小,潜热输送占主导地位。动量通量和摩擦速度均在风速较大的下午较大,风速小的早晨小。     

A New Parameterization of Canopy Radiative Transfer for Land Surface Radiation Models

A new parameterization of canopy asymmetry factor on phase function,which is dependent on the leaf normal distribution and leaf reflection/transmission,is derived. This new parameterization is much more accurate than the existing scheme. In addition,the new solutions for both the diffuse and direct radiation can be obtained using the Eddington approximation. It is found that the direct radiation can be described as a function of the diffuse radiation. This new approach offers a substantial improvement in accuracy,as compared with the hemispheric constant method,for both isotropic and anisotropic cases. Given the analytical nature of the solution and its high accuracy,we recommend the new parameterization for application in land surface radiation modeling.     

伸展域构造变换带内部构造类型研究

分别从传递带和调节带两个方面论述了构造变换带内的构造类型，将传递带内的构造类型分为传递断层等四种类型，将调节带内的构造类型划分为背斜等四种类型。分析了传递带与调节带内各构造类型的发育条件、几何形态特征以及它们之间的相互关系。研究认为，传递带和调节带内的构造类型主要取决于其发育位置处的构造背景及边界控制条件。     

陕西镇安丘岭微细浸染型金矿床金矿化过程中元素活动规律

通过对比丘岭矿区采于同一层位、同一岩性的岩石一矿石的地球化学组成，应用质量平衡方程对该微细浸染型金矿床不同的岩石类型在金矿化过程中元素活动规律的计算结果表明，不同类型的岩石在矿化前后元素的迁入或迁出状况不同、质量盈亏情况不同，碎屑岩岩石矿化后其质量增加，碳酸盐岩石矿化后质量发生亏损；金矿化发生时，含矿溶液为一富SiO2富K^ 的酸性溶液，且金矿化发生于较为还原性的环境。