Numerical Simulation On Characteristics Of Reentrance Sea Typhoon And Modeling Factors Study

Numerical model is an effective tool to simulate and predict typhoon track, intensity, structure and environmental factors, which directly affect the forcasting results. In China WRF (Weather Research Forcast) is widely used in the typhoon forcasting. Here we use the mesoscale model WRF to simulate the reentrance sea typhoon, comparing the impact of different modeling factors.Typhoon Wipha (No.0713) and typhoon Mindulle (No.0407), are both typical reentrance sea typhoons. Typhoon Wipha landing in Zhejiang, goes northward into Jiangsu. It is strengthen again after into the Yellow Sea. Typhoon Mindulle land in Zhejiang, soon from the Hangzhou bay into the East China sea. We take the two typhoons for simulating, consideration of the development of the upper thermal factors-the microphysics schemes, the influence of thermal factors-sea surface temperature, as well as the typhoon3d wind field structure of the commissioning of the dynamic factors-typhoon bogus scheme. Explore these factors in the simulation result of the typhoon path and strength.In this paper, we use the invariable sea surface temperature, daily average and six hours of change SST to simulate. As the differences of the ice scheme in the big body of the typhoon, we choose WSM6and PLIN model microphical schemes. Well, Bogus scheme changes model wind pressure initial field. Through the impact factor of several corresponding configuration numerical experiments, this paper discusses the influencing factors of dynamic, thermodynamic typhoon path and strength of numerical simulation of comprehensive effect.To focus on the respective response of the schemes to the different SST fields and the schemes impact on the simulated typhoon track and intensity. The results showed that the SST changing with time can help to better diagnose and simulate air-sea interaction, and to improve the prediction of typhoon track and intensity. For the simulation of typhoon Wipha, the scheme WSM6is more suitable than scheme PLIN according to a summary of typhoon track, central air pressure, the biggest wind speed, sensible heat and latent heat in the stages of typhoon landing and reentrance sea. But to typhoon Mindulle, PLIN gives a better track, WSM6shows well on the whole. The TC Bogus scheme didn’t show a better comprehensive effect and needs further in simulation typhoon Mindulle. During the stage of typhoon reentrance sea, the simulated sensible heat and latent heat distribution at air-sea interface showed that the positive high value part provides energy to typhoon, and indicates typhoon track in advance. The high value part of latent heat is located at the typhoon wind convergence and strengthen area. The high latent heat part in the typhoon structure system provides the contribution to maintain the reentrance sea typhoon activity.