多普勒雷达资料同化在台风“灿都”(2010)预报中的应用研究

Experiments of assimilating Doppler radar data in forecast of Typhoon Chanthu

文章基于中尺度天气预报模式(WRF)及其三维变分同化系统(WRF-3DVAR),采用了两部雷达径向风资料,进行单一时间分析以初始化台风"灿都"(Chanthu),比较研究了同化雷达径向速度(Vr)对台风"灿都"分析和预报的影响。结果表明:同化雷达径向风的作用主要体现在台风强度和环流结构的调整,且在同化达到一定时长后,对改进同化后的预报分析有积极效应。同化试验改进台风的初始风场以及台风环流中心的热力和动力结构、强度和位置,进而提高18h预报的台风结构、路径、强度。

Based on the WRF (Weather Research and Forecast) model and WRF-3DVAR (3-Dimensional Variational) assimilation system, we conduct a single time analysis to initialize Typhoon Chanthu and compare the effects of assimilation radar radial velocity (V r ) on Typhoon Chanthu analysis and forecast, with two radar radial wind data. We show that the role of assimilating radar radial wind is mainly reflected in the adjustment of typhoon intensity and circulation structure;and after the assimilation reaches a certain length of time, it has a positive effect on the improvement of forecast. The assimilation test improves the typhoon's initial wind field and the thermal and dynamic structures, intensity, and location of the typhoon circulation center, thereby improving the typhoon structure, path, and intensity predicted for future 18 hours.