台灣與周邊地區雷達遙測應用於氣象防災的技術開發,驗證與應用-同化雷達等觀測資料短期預報台灣與周邊地區劇烈降雨的技術研發與驗證(總計畫及子計畫一)(III)

This proposal is a sub-project of an integrated project, which is based on the 2019 disaster prevention policy released by MOST with the purpose of developing radar data QC procedures and advanced data application technologies. The goal of this sub-project is to improve the radar data retrieval methodology so that high spatiotemporal resolution of three-dimensional meteorological fields over complex terrain can be retrieved. By using these high-quality data sets, it is possible for researchers to identify the key factors controlling the evolution of the convection, and design proper high-resolution data assimilation technique to conduct short term forecast of severe weather events.In recent years the applicant has developed a multiple-Doppler radar wind synthesis method WISSDOM (WInd Synthesis System using Doppler Measurements). WISSDOM is capable of using data collected by any number of weather radar, and merging wind information from mesoscale model forecast, surface station, radiosonde, wind profiler, and low level wind over ocean derived by satellite, to synthesis the flow field along radar base line as well as overcomplex terrain. WISSDOM is particularly useful in analyzing wind fields over Taiwan’s complex topography and vicinity area. By using the three-dimensional wind field from WISSDOM, the applicant has developed an algorithm to directly retrieve the thermodynamic fields (including pressure and temperature perturbation) over terrain, and measure the water vapor field. Then, the observed and retrieved three dimensional meteorological parameters will be applied to initialize a high-resolution numerical model. In this research multiple representative real cases will be selected and tested so that one can evaluate the improvement of the model ability in forecasting severe rainfall events in mountainous regions.