使用單一都卜勒雷達資料反演三維風場

The Retrieval of Three-dimensional Wind Field Using Single Doppler Radar Data

廖宇慶(Yu-Chieng Liou) ； 章鶴群(Ho-Chin Chang)

《大氣科學》 32卷1期 (2004/03) Pp. 41-56

摘要

本研究提出一種利用單一都卜勒雷達密集觀測的徑向風及回波，反演三度空間中完整三維風場（u、v、w）的方法。為測試此反演方法的精確度，研究中的雷達觀測資料係利用數值模式產生的理想資料模擬而成。初步的分析結果顯示，此方法應用在三維空間中的反演確實是可行的。尤其是對於垂直速度(w)的反演，由於本方法採行的是同時反演所有的未知風場參數，其效果會優於若干其它研究中所採用的兩段式解法。基本上，此種所謂的兩段式解法會先計算水平風場，再經由對連續方程式的積分計算垂直速度。此外，本文亦討論了當係統有無水平移速時對反演結果的影響。

關鍵字

都卜勒雷達 ； 反演

並列摘要

This research proposes a method whereby the three-dimensional wind fields ( u, v, w) in a three-dimensional space can be retrieved using radial wind and reflectivity data observed intensively by one Doppler radar. In order to evaluate the accuracy of this method, the radar data are obtained from an idealized numerical model simulation. Our initial analyses indicate that the application of this method to a three-dimensional space is indeed feasible. In addition, the quality of the retrieved vertical velocity (w) is particularly encouraging. Since our method recovers all three wind components simultaneously, its performance is found to be better than some two-step type methods employed by other research. Basically, in these so-called two-step methods, the horizontal wind fields are computed first, followed by an integration of the continuity equation to estimate the vertical velocities. The influence of the system moving speed to the retrievals is also discussed in this study.

並列關鍵字

Doppler radar ； retrieval