Abstract:According to the wind shear events reported by aircrafts at Dali Airport in 2016 and 2017, the wind shear at Dali Airport is analyzed by using the automatic meteorological observation data and wind profiler radar data in relevant periods. The results show that: (1) Wind shear occurs from November to April of the next year, mostly in January and February, mainly in 07:00 to 13:00, half in sunny days, and 83% below 350 m. (2) The wind shear below 100 m has gust winds on the ground, and the maximumminimum difference of wind speeds is more than 6 m/s. Six wind shear events occurred in the range of 15 to 91 m. The wind direction at one end of the five wind shear reports varied by more than 180 degrees. The ground winds at the north and south ends had opposite winds, and the difference of wind speeds was obvious. AWOS (Automated Weather Observation System) captured significant changes in wind direction and velocity, which can provide reference for early warning of nearsurface wind shear. (3) When a wind shear occurs at a high altitude, there is a difference of wind speeds (>8 m/s) between the upper and lower layers of radar data, which can determine the exact height, start time and end time of discontinuous upper and lowerlayer winds. (4) The airport area is often under the situation of large ground wind speed and small upper air wind speed or small ground wind and large upper air wind speed, so the combination of ground wind and wind profiler radar data can provide reference for the preliminary early warning of low altitude wind shear in the future.
