Analysis Verification And Numerical Simulation Of Rainstorm Caused By Typhoon Fanapi

Fujian is an area which Typhoon landing frequency, serious influence by Typhoon rainstorm.The interaction between the coastal areas of Fujian and the Strait of Taiwan special terrain always produce unconventional effect on the Development of Typhoon, in this kind of situation, the physical mechanism of typhoon rainfall become more complex, it is difficult in practical forecast. In order to further reveal the circulation situation, water vapor condition, dynamic condition, terrain, the asymmetric structure of the typhoon rainfall distribution characteristics, by using NCEP reanalysis data, ECMWF reanalysis data, satellite data, Radar data, regional automatic weather station data and so on observation data, and by using the WRF numerical model,the analysis verification and numerical simulation of the rainstorm caused by "Fanapi" are processed.After a preliminary analysis on live and circulation characteristics of the typhoon "Fanapi",we found because the subtropical high situation changes and the coastal areas of Fujian and the Strait of Taiwan terrain affect, the path of typhoon "Fanapi" is twists and turns,and the rainstorm concentration.By using the WRF model, a high resolution numerical simulation to carry out on the process of the typhoon "Fanapi". The results show that:Simulation of the typhoon process of this model is successful and credible.By using the High resolution data and radar data, satellite observation data,the analysis verification are carried out on the physical mechanism of typhoon "Fanapi" rainstorm generation.We can get the main reason of the typhoon rainstorm as follows:1.The interaction between the western continental subtropical high and the eastern south airflow is the main scale circulation system to effect the rainstorm caused by typhoon "Fanapi".2. Abundant water vapor transport, coupling dynamic action between low and high, strong ascending motion, all of them play a key role on the occurrence and maintain of the rainstorm.3. The effect of increase rainstorm is very obvious as the resule of the special landform in southern Fujian.4. When the typhoon across Taiwan, the main precipitation cloud to the fourth quadrant is an key reason on cause heavy rain.Comparison of the forecast results among the FJ-WRF model and T639model and GSM model,we can find that all of the three mode numerical prediction on the rainstorm area of "Fanapi" has a useful reference value, and the latter two mode numerical prediction on the rainstorm magnitude has a better useful reference value, in order to achieve better effect, we must be use together of mode numerical prediction and statistical prediction and subjective forecast.