基于自动气象站和风廓线雷达资料的大理机场风切变分析与应用

Analysis and Application of Wind Shear at Dali Airport Using AWS and Wind Profiler Radar Data

根据2016-2017年大理机场航空器报告的风切变事件,利用同时段的自动气象观测资料、风廓线雷达资料对大理机场风切变进行了统计和分析。结果表明:(1)风切变均发生在每年的11月至次年4月,1月、2月最多;主要发生于07:00-13:00,一半出现在晴天;发生在350m以下占83%。(2)100m以下的风切变,地面均有阵性风,最大最小风速差>6m/s;发生在15~91m的6次风切变,5次报告风切变的一端风向变化超过180°,南北两端地面风出现对头风,风速差异明显。AWOS(Automated Weather Observation System)捕捉到风向风速的明显变化可为近地层风切变预警提供参考。(3)发生在高度较高的风切变,雷达资料在遭遇风切变高度的上下层存在≥8m/s风速差,能确定上下层风不连续的准确高度、开始时间和结束时间。(4)机场区域常出现地面风速大而上空风速小或地面风速小而上空风速大的情况,结合地面风和风廓线雷达资料可为今后低高度风切变的初步预警提供参考。

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 th a t:(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 near-surface 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 upperand lower-layer 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.