摘要
多普勒天气雷达是研究中小尺度天气系统的重要工具 ,但却只能提供风场的径向速度 ,因而必须通过风场反演技术来求解二维或三维风场。详细分析了各种单部、多部和多基地多普勒天气雷达风场反演技术及其优缺点 ,同时指出了应重点研究的方向。从反演结果来看 ,基于变分法的反演技术明显优于其它方法 ,这是今后的一个主要研究方向 ;利用四维同化理论 ,在数值模式初始场中使用反演数据 。
Doppler weather radar is one of the most powerful tools for investigating severe mesoscale and microscale weather systems. But a main limitation of Doppler radar is that it only measures the radial component of the wind vector. So the two dimensional or three dimensional velocity must been retrieved by way of wind recover technology in order to study the weather systems. The full 3D wind field is extreme important for diagnostic research studies, hazard warning, as well as numerical forecasting. This paper introduces the wind field retrieval techniques based on the single Doppler radar, multiple Doppler radar and bistatic multiple Doppler radar, analyses their merit and demerit and addresses the future research. In recent years, many theories of single Doppler radar retrieval were proposed. The VAD technique, VVP method and VAP method use radial velocity data to retrieve horizontal wind field, but they are limited to cases where the wind field is smooth and linear. Use of one single moving frame can not properly account for the advection of scalar fields in different regions. A scheme with two or more moving frames of reference might be helpful in retrieval. Methods based on the variation are the direction of the future research. Wind and thermodynamic analyses can potentially be used as high resolution data source for numerical weather models. Several attempts show that it improves the forecast accuracy in the high resolution numerical models initialized with Doppler radar retrieval data. For dual Doppler retrieval, simple formulas were obtained for the horizontal wind components, while the vertical velocity component was found to satisfy the air mass continuity equation. The roots of most modern day dual Doppler analysis techniques are based upon this pioneering investigation. Dual Doppler radar wind recover techniques improve the result accuracy obviously as compared to the single radar retrieval. But several factors can lead to errors. These factors include contamination of radial wind data(due to
出处
《地球科学进展》
CAS
CSCD
2002年第3期384-390,共7页
Advances in Earth Science
关键词
多普勒天气雷达
多基地天气雷达
风场反演
Doppler weather radar
Bistatic multiple Doppler radar
Wind retrieval.
