多普勒天气雷达识别低空风切变算法的改进研究

Study on improvement of algorithm for identifying low-level wind shear by Doppler weather radar

针对CINRAD-CD天气雷达切变线识别产品的局限性,通过对探测资料采取中值滤波、滑动平均等预处理方法,有效填充缺测区探测资料。随后,再对探测资料采用最小二乘拟合法计算得到风场径向速度的径向切变、方位切变及垂直切变,进一步得到风场径向和方位的组合切变,从而得到垂直切变图。通过两次银川降雨过程实例应用,证明上述方法能够较准确地辨识风切变线,可为临近预报提供更科学的参考信息。

In view of the limitations of shear line identification products of CINRAD-CD weather radar,the detection data in the missing detection area are effectively filled by means of median filtering,moving average,and other preprocessing methods.Then,the radial shear,azimuthal shear,and vertical shear of the radial velocity of the wind field are calculated by using the least square fitting method,and the radial and azimuthal combined shear of the wind field is further obtained,so as to obtain the vertical shear diagram.Through the two examples of precipitation process in Yinchuan,it is proved that the above method can identify the wind shear line more accurately and can provide more scientific reference for nowcasting.