基于多普勒天气雷达数据的中层径向辐合自动识别及其与强对流天气的相关性研究

发布时间：2019-05-10 10:52

【摘要】：本文提出了一种从多普勒天气雷达单仰角径向速度图中的正-负速度区域对入手自动识别一类强对流天气的中层径向辐合的方法.首先,根据雷达探测机理,解释了由气流形成的辐合场一定会在径向速度图中形成局部最大正速度区域和局部最大负速度区域的特点,然后构建正-负速度区域对的识别算法,通过来自多个单仰角径向速度图的区域对配准和相关信息,判断雷达径向速度图中是否存在着中层径向辐合,推算辐合的强度、延伸厚度等重要参数,确定得到最优垂直剖面图的剖切方位.经对客观存在显著中层径向辐合的384例样本和不存在明显中层径向辐合的356例样本的测试,本文方法对显著中层径向辐合的识别率达到100%、误识率为0,与人工方法相比,本文方法把对中层径向辐合的识别时间从分钟级缩短到秒级,同时自动给出其强度、高度、厚度、位置等丰富的定量信息和恰当的可视化垂直剖面图.利用给出的参数信息进行了与强对流天气的相关性研究,验证了中层径向辐合与对流行地面大风的较强相关性,同时发现,最强中层径向辐合的高度对区分强冰雹与强降水、中层径向辐合的强度对估计冰雹尺寸具有良好的指示性.
[Abstract]:In this paper, a method for automatically identifying the middle radial convergence of a class of severe convective weather is presented, which starts with the positive and negative velocity region pairs in the single pitching angle radial velocity diagram of Doppler weather radar. Firstly, according to the radar detection mechanism, it is explained that the convergence field formed by air flow will certainly form the local maximum positive velocity region and the local maximum negative velocity region in the radial velocity diagram, and then the recognition algorithm of the positive and negative velocity region pairs is constructed. Through the region pair registration and related information from multiple single angle radial velocity maps, it is judged whether there is middle radial convergence in radar radial velocity map, and the intensity and extension thickness of convergence are calculated. The cutting orientation of the optimal vertical profile is determined. 384 samples with significant radial convergence of middle layer and 356 samples without radial convergence of middle layer were tested. The recognition rate of radial convergence of significant middle layer is 100%, and the error rate is 0. Compared with the artificial method, the recognition rate of radial convergence of significant middle layer is 100% and the error rate is 0. Compared with the artificial method, the recognition rate of radial convergence of significant middle layer is 100% and the error rate is 0. In this paper, the recognition time of radial convergence in the middle layer is shortened from the minute level to the second level, and the abundant quantitative information such as intensity, height, thickness and position and the appropriate visual vertical profile are given automatically. The correlation between the radial convergence of the middle layer and the strong ground gale is verified by using the given parameter information, and it is found that the height of the strongest radial convergence of the middle layer distinguishes the strong hail from the heavy precipitation. The intensity of mid-level radial convergence is a good indicator for estimating hail size.
【作者单位】：天津大学电气与自动化工程学院;
【基金】：天津市自然科学基金(批准号:09JCYBJC07500) 公益性行业(气象)科研专项基金(批准号:GYHY200706004) 中国气象局新一代天气雷达建设软件系统开发及应用项目资助的课题~~
【分类号】：TN959.4

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