The effect of the horizontal structure for symmetric tropical cyclones on their movement

In this paper, using Holland's method, the effect of the horizontal structure of tropical cyclones on their motion is investigated. The "characteristic radius", r_o characterized as the horizontal structure of a tropical cyclone,
r_c=1/2(1+√1+(2(m+2))/p)r_M
in which m and p are the parameters of the vortex, has been found by the author. And then it has been shown that there is but one "characteristic radius" for each cyclone with horizontal structure. Two direct analytic solutions for the uniform and non-uniform basic flows in steady situations are presented with r_c Results show that the change in the horizontal structure of the tropical cyclone itself will have obvious effect on the cyclone motion, on both its direction and speed. Therefore it must be considered in the research on the tropical cyclone motion.