双多普勒雷达风场反演误差和资料的质量控制
Error Estimation in Wind Fields Derived from Dual-Doppler Radar and Data Quality Control
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摘要: 提出了用双多普勒雷达观测资料进行回波强度、径向速度和方位定位的质量控制方法,以及利用概率分布法订正配对的双多普勒雷达回波强度的方法。以2001年973“中国暴雨”外场试验期间获取的双多普勒雷达观测资料为例,比较了合肥、马鞍山和宜昌、荆州的两对双多普勒雷达同步观测的回波强度、径向速度和方位的改变对观测数据对比的影响;分析了这两对双多普勒雷达径向速度测量误差引起的风场反演的误差。结果表明:两对双多普勒雷达观测的回波强度和径向速度的空间位置和变化趋势比较一致,合肥与马鞍山雷达的回波强度有一定差异,径向速度也有1~2 m/s的差异。风场反演的误差与风场的方向、大小、空间位置等有关。在两个径向速度夹角在40°~140°范围内,共面上的风场的反演误差在1~2倍的雷达探测径向速度的误差范围内。Abstract: The method for quality control of dual-Doppler radar reflectivity, radial velocity and azimuthal location is introduced. The reflectivity correction approach with probability distribution method is presented. The two dual-Doppler radar systems in Hefei and Ma’anshan, Anhui Province, Yichang and Jiangzhou, Hubei Province, were used to observe the wind structure of the precipitation systems in the China Heavy Rainfall Experiment and Study in 2001. The reflectivities and radial velocities from the dual-Doppler radar are compared and the effect of azimuth location on dual-Doppler radar data is analyzed. The errors of wind derived from the two Doppler radar systems are estimated. The results show that the patterns of reflectivity and radial velocity measured by the Doppler radar systems are similar; but the values of reflectivity measured at Hefei and Ma’anshan are obviously different; the deviation of velocity measured by the two radars is 1-2 m/s. The error of wind derived from dual-Doppler radar is relative to wind direction, speed and position. The error is within 2 times of the measurement error of radial velocity in the area where the angle between the two radial velocities is in 40o-140 o. These results are valuable for the use of the dual-Doppler radar data and the observation by dual-Doppler radar.
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Key words:
- Dual Doppler radar;
- Error analysis;
- Quality control
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表 1 多普勒雷达系统主要参数
表 2 马鞍山、荆州雷达不同旋转角度时配对雷达1 km×1 km格点上回波的标准差和相关系数
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