中文摘要：

An f-plane quasi-geostrophic barotropic vorticity equation model of high resolution is designedin this paper in order to investigate the characters of vorticity propagation and the effect ofnonlinearity on the propagation within a typhoon circulation,wherein two mesoscale vorticescoexist at different radial positions.The results of 10 sets of experiments suggest that incomparison with only one vortex,the intensity of the inward propagations of vorticity strengthensdistinctly,vorticity detains in the inner region of typhoon circulation for a longer time,and thelocal maximum wind speed in the inner region increases clearly.The introduction of nonlinearadvection into the model weakens the intensity of both inward and outward propagations ofvorticity,but makes the inward propagation up to a position closer to the center of typhoon.