| Tropical cyclone tracks and intensity change are two important aspects in typhoon forecast. For a few decades, a notable evolution has been obtained in the forecast of tropical cyclone tracks, relatively, TC intensity forecast has been obtained smaller improvement. Since the 1990s, the physical mechanism of tropical cyclone intensity change has been a forward topic of typhoon dynamics. Montgomery and Kallenbach proposed that the propagation of vortex Rossby waves may intensify the tropical cyclone, this new physical mechanism has been widely studied.Firstly, this paper designs a polar coordinate barotropic vorticity equation semi-spectral model and a quasi-geostrophic grid model in order to research the propagation of vortex Rossby waves and tropical cyclone intensity change entirely. Secondly, a shallow-water model is designed to study the topographical effects on the propagating vortex Rossby waves and tropical cyclone intensity change detailedly.The main conclusions show as following:1 The effects of propagating vortex Rossby waves on TC intensity change are relative closely to the position, the size and intensity of the initial disturbance. The phenomena of initial disturbance vorticity translating into spiral bands is most evidently for it locating at the periphery of Radius of Maximum Wind(RMW), near RMW next and the spiral bands vanish when it is positioned in the inner core region. Indicating that the farther the distance from the TC center, the more distinctly the spiral bands and the opposite is true. The most distinct intensification in maximum azimuthally mean tangential velocity occurs when the convective patch is positioned in RMW, the second in the interior region. This intensification exhibit distinct vibration with 6~7h period and the vibration in inner region diminishes with shorter period. The deceleration occurs with initial asymmetry in outside region of RMW with 13h period and the amplitude reduces with time. The smaller convective patch corresponds to slight changes of maximum mean wind speed and the larger convective patch corresponds to the waves amplifying, the intensity of the inward propagation of vorticity strengthening distinctly, the amplitude of velocity change increasing and the period longing. The disturbance located at inner region and near eyewall intensifying corresponds to the growth of amplitude of typhoon maximum tangential velocity with shorter period and the opposite is true. The weakening role of periphery disturbance intensity drop in typhoon maximum tangential wind reducesIVRossbyobviously and the mean tangential wind display a strong vibrational characteristic for the periphery disturbance intensity growth. For two mesoscale vortices coexisting, the disturbance outside RMW diminishes the intensifying role of near eyewall disturbance on TC intensity. The two mesoscale vortices for east-west distribution are similar to azimuthally wave number two and intensify TC more strong than other two vortices distributing and weaker than actual azimuthally wave number two waves disturbance. The introduction of nonlinear advection into the model weakens the intensifying of maximum tangential wind with relative to the initial disturbance azimuthally wave numbers and intensity .2 An f-plane quasi-geostrophic barotropic vorticity equation model of high resolution is designed in this paper in order to investigate the characters of vorticity propagation and the effect of nonlinearity on the propagation within a typhoon circulation, wherein two mesoscale vortices coexist at different radial positions. The results of 10 sets of experiments suggest that in comparison with only one vortex, the intensity of the inward propagation of vorticity strengthens distinctly, vorticity detains in the inner region of typhoon circulation for a longer time, and the local maximum wind speed in the inner region increases clearly. The in of nonlinear advection into the model weakens the intensity of both inward and outward propagation of vorticity, but makes the inward propagation u...
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