关键词: 激光测风雷达, 低空风切变, 告警算法, 区域散度法, 斜坡检测法

Abstract:  Based on the wind lidar observation data and 12 wind shear events reported by pilots at Lanzhou Zhongchuan airport from July to November 2020, the performance and effectivity of two lidarbased lowlevel wind shear alerting algorithms were investigated. One algorithm is the regional divergence algorithm (RDA), and another is the combinational algorithm of single ramp and double ramps detection. The IRIS algorithm, the default algorithm in the lidar, was used as a reference. The conclusions are as follows: (1) RDA and ramp detection algorithm had better ability in alerting wind shear events under the convection weather or downward momentum weather conditions. However, they had a poor performance on identification of wind shear events under turbulent conditions. (2) Compared with ramp detection algorithm, RDA uses multiradial directions to reconstruct headwind profile, and consequently it can provide some temporal and spatial evolution information of radial velocities along the runway and its extension line, which is conducive to identification and alerting of wind shear events ahead of time. (3) The alerting results on 12 wind shear events indicated that RDA was superior to ramp detection algorithm and IRIS algorithm.

Key words: wind lidar, low-level wind shear, alerting algorithm, regional divergence algorithm, ramp detection algorithm