Simulation Studies Of Typhoon Pressure And Wind Fields Based On Multiple Models Of Putuo District, Zhoushan

According to the moving path, typhoons that affect Putuo district, Zhoushan could be divided into two categories, landing and steering types. And each type could be further divided into three small species depending on the location of its landing points or steering points. Giving an incomplete statistics of the incidence levels that typhoons brought to the sea area around the Putuo district, Zhoushan, we could come to the conclusion that it is much easier to lead to a more serious damage when the typhoon landed on Zhejiang Province and the path of it is D1type or the typhoon steered in the offshore that in west125degrees and north25degrees of the Zhejiang Province and the path of it is Z1type. Therefore, these two types of typhoons should have been the key researching objects of the numerical simulations of typhoon storm surge in Putuo district, Zhoushan.During the process of the numerical simulations of typhoon storm surges, the stand or fall of the simulation and forecast accuracy is directly related to the precision of the simulation of typhoons’ pressure and wind fields. At the same time, the hind-casting of typhoons’ pressure and wind fields could complete the lack of the actual observation data. The key point of typhoon hind-casting is to calculate the distribution of the typhoons’ pressure and wind fields by using mathematical models and typhoon elements, such as the moving path, the central pressure, the maximum wind speeds and the radius of the maximum wind speeds etc.This paper chose the No.1211and the No.9806typhoons as the calculation cases, and the Fujita model, the Jelesnianski model and the Meng model as the typhoon simulation models to calculate the pressure and wind fields of two typhoons. And then gave comparison and analysis of the consequences to find that which model is the most suitable to the Putuo district, Zhoushan. It is shown by the hindcasting consequence that all the three models could be used to simulate the pressure field of typhoon since the Fujita model got to a better simulation of the internal pressure distribution. And for the simulation of typhoon wind field, with validation of the combination of simulation data and measured data, we could find that compared with the other two typhoon models, Jelesnianski model could get a more effective and applicative simulation of the pressure and wind fields of typhoon that affected the Putuo district, Zhoushan. Then we could get to the point that in the actually numerical simulation of typhoon storm surge in sea area around the Putuo district, it is doable to use the Fujita model to get the pressure data and the Jelesnianski model to calculate the wind data in order to obtain more appropriate and accurate data.