【摘要】 本文采用正压原始方程模式对不同强度、间距和基本气流条件下的双台风涡旋作了一系列数值试验,试验结果表明:在无环境风场条件下,双台风在某一临界距离内作明显的相互旋转运动,这个临界距离是随台风强度以及风场分布的特征而改变的。双台风有明显的相互吸引作用的临界距离远小于相互旋转的临界距离。双台风相互旋转速率与台风强度成正比、与台风切向风速向外减小率和台风中心的间距成反比。均匀的环境气流对双台风相互作用影响甚微,但有了基本气流以后,两个台风对基本气流的扰动具有不同敏感性。在西风基本气流中,西台风移动稳定而东台风移动稳定性差。在有切变的环境气流中,台风运动既受环境气流的平流作用也受β效应作用和台风相互作用,当台风中心间距大于相互旋转的临界距离时,主要受环境气流和β效应作用。此外,本文还把试验结果与西北太平洋的台风统计资料作了比较,並讨论了试验结果对预报的启示。更多还原

【Abstract】 A series experiments of different intensity of tropical cvctone, separation distance and basic flow have been carried out with a barotropic primitive equation model in order to investigate the mutual rotation and the attraction of two tropical cyclones and their motion in environmental flow.The results from the ex-permients indicate: the binarv tropical cyclones within a certain critical distance rotate evidently (more than 10 everv 12 hours) under the condition of no environmental flow, the critical distance varies with the intensity and the characteristics of wind fields of the two tropical cyclones; the distance, within which two cvclones are evidently attracted) is much shorter than the critical distance of mutual rotation.It is shown that the rate of mutual rotation of two tropical cvclones is proportional to the intensity of tropical cvclone and reve-rSely proportional to the ratio with which the tangential wind velocitv decreases and the square of the separation distance of two cvclone centers.It is also shown that an uniform environmental flow has no evident effect on the interaction between two tropical cyclones,and two tropical cyclones have different Sensitivities to the disturbances of basic flow. The West cyclone propagate steadily in a west basic f low,but the east cyclone shows a relatively unsteady trajectory. When the velocity of steering flow increases,the two tr-opical cyclones move more stablv.Under a condition of shearing environmental flow,the motion of tropical cyclone is affected by the advection of the environmental flow, β effect and the mutual interaction of two tropical cyclones. when the separation distance between two cvclone centers is longer than the critical distance,the motion of tropical cyclone is mainlv affected by the environmental flow and β effect.更多还原