EFFECT OF ENERGY DISPERSION ON THE STRUCTURE AND MOTION OF TROPICAL CYCLONE          下载免费PDF全文

罗哲贤 《Acta Meteorologica Sinica》1994,(1)

The energy dispersion of a typhoon vortex and its effect on the typhoon motion are studied using an analyticalmethod of double-Fourier expansion as well as a numerical model in a β-plane nondivergent barotropic framework.The analytic model and the linear version of the numerical model give essentially the same result:the energy dispersionfrom a tropical cyclone can creat an L-H-L wave train to the east of the tropical cyclone.Three numerical experiments,integrated for 7 model days by the nonlinear model,indicate that the closed high in the wave train produces obvious in-fluence on the structure and movement of the tropical cyclone.  相似文献   

CONTOUR DYNAMICS FOR VORTEX MOTION INFLUENCED BY THE CORIOLIS FORCE          下载免费PDF全文

罗哲贤 《Acta Meteorologica Sinica》1994,(1)

The computational formulae are given for single-contour constant-value vortex motion influenced by the Coriolisforce in the framework of contour dynamics,by which four numerical computations are performed,the result exhibitingtheir validity.  相似文献   

边缘区域扰动演变对台风结构的影响   总被引：8，自引：3，他引：8  

罗哲贤 《大气科学》1994,18(5):513-519

在台风环流边缘区域给出不稳定模态的扰动四波分布作为初始场，用准地转正压模式实施四组数值积分，研究了边缘区域扰动演变及其对台风非对称结构及外区流型的影响。结果表明:线性平流对于外缘区域扰动的发展起主要作用。β项导致一个气旋—反气旋涡旋对和非对称结构的形成。非线性平流则使外缘区域较小尺度的涡旋破碎，形成更小尺度的涡旋。在线性平流、β项和非线性平流的共同作用下，台风结构与外区形成象螺旋云系的分布。外缘区域扰动引起的结构变化，进而能影响到台风的移动路径。  相似文献   

NUMERICAL SIMULATION OF TROPICAL CYCLONE MOVEMENT WITH THE RELATED CRITICAL POINT PHENOMENON          下载免费PDF全文

(罗哲贤) 《Acta Meteorologica Sinica》1994,(2)

A study is made of the paths of tropical cyclones under the joint action of environmental flow and heating fields interms of a quasi-geostrophic barotropic model with the thermal forcing and dissipation terms involved,in which 16 ex-periments are designed and integrated for more than 7 model days.Results show that for different parameter values ofthe environmental flow and heating field,and the cyclone scale, such paths as counterclockwise looping, zigzag form andwestward march with an abrupt turning towards the north are reproduced clearly in the model atmosphere,exhibitingtheir critical points of nonlinear character.  相似文献   

ABRUPT CHANGE OF FLOW PATTERN IN BAROCLINIC ATMOSPHERE FORCED BY JOINT EFFECTS OF DIABATIC HEATING AND OROGRAPHY   总被引：1，自引：0，他引：1  

罗哲贤 《大气科学进展》1987,(2)

Based on the catastrophic theory, the possible causes of abrupt change in the atmospheric circulation over the Northern Hemisphere during June and October have been explored by Li and Luo (1983) and Miao and Ding (1985). However these studies are confined to the barotropic atmosphere without consideration of orography. The purpose of this paper is to further study the physical mechanism of the abrupt change of flow pattern within the baroclinic atmosphere in the presence of orography. Results show that the abrupt change of flow pattern can be stimulated by the gradual variation of a diabatically heating parameter, which is similar to the observed fact about the rapid shift of position of the subtropical high center in the upper troposphere along the zonal direction during seasonal transition from the summer half year to the winter one.  相似文献   

大尺度大气运动的形态与耗散结构     

罗哲贤 《气象学报》1986,44(2):140-148

Lorenz低谱途径,作为一种简化方式,满足丑纪范提出的简化大气动力学方程组的准则。准地转斜压波和地形驻波是大尺度大气运动的两类重要形态,它们都具有耗散结构的特色。  相似文献   

一个以全露点温度为湿度变量的低谱湿模式     

罗哲贤 《干旱气象》1985,(4)

(一)1.研究古气候和气候变迁问题的一个有力的途径是实施数值试验。目前,在数值模拟试验中,广泛地使用了大气环流模式(GCM)。对气候平均场和短期气候变化的模拟取得了引人注目的结果。这些显示了 GCM 广泛应用的前景。2.无论是谱展开,还是差分方法,基本方程组都被转化为一个强迫耗散的自治的或非自治的非线性系统。古气候和气候变迁的问题,是气候学的课题。当我们用数值模拟的途径去  相似文献   

红河断裂的第四纪活动研究(二)——断裂活动特征、滑动速率与地震重复周期探讨     

C.R.艾伦  韩源  K.E.西  张步春  A.R.格拉斯比  朱成男 《地震研究》1984,(2)

自红河及其支流开始下切延续至今(约75万年),断裂似乎经历了5—6公里的右旋滑移,我们采用可能的最大切割速率,估计出断层平均滑动速率约为7毫米/年。在这种长期滑动作用下,沿断层观测到最小一级的水平断错是4—9米。如果将这种断错看作一次地震事件,那么,地震平均每500年至1200年可能发生一次。这一点与过去历史记载里近300年内在该断裂上无强震活动是一致的。  相似文献   

我国半干旱地区降水量序列信噪比分析   总被引：3，自引：0，他引：3  

马镜娴  红梅  罗哲贤 《干旱气象》1989,(3)

本文提出降水量序列信噪比的概念,分析了我国半干旱区降水量序列信噪比的空间分布及代表站点信噪比取值随时间的变化特征。  相似文献   

从工程地貌学到生态地貌学研究     

西.  ЮГ  刘吉成 《国土资源信息化》1995,(4):7-10

  相似文献