乌鲁木齐国际机场风切变颠簸天气个例分析

Analysis of a Wind Shear at Urumqi Airport

利用常规天气资料、风廓线雷达探测资料、自动站资料、NCEP再分析资料及数值模拟资料,对乌鲁木齐2010年12月2—3日对飞行安全有较大影响的风切变颠簸天气进行了多角度分析。结果表明,局地性东南风层的形成和下传造成的水平方向上非东南风与东南风的切变、锋区南压过程中在北疆沿天山一带低空诱发的小范围风场扰动对东南风层短暂破坏而引起的水平和垂直方向上风向风速的迅即变化,是造成机场附近风切变颠簸的原因。中尺度数值预报模式(WRF)对此次风切变天气有较好的模拟能力,有助于在探测资料有限的情况下了解风切变的细微结构及其演变。

A strong wind shear case that occurred at Urumqi Airport during December 2-3 , 2010 was analyzed using routine meteorological data , wind profile radar data , automatic weather station data , NCEP reanalysis data and numerical simulation results data. The results show that wind shear occurred at such weather situations as following：polar front frontal zone slowly moved southwards to Xinjiang area , the inversion in the basin of the north of Xinjiang maintained stability and there was local low-level southeast wind at Urumqi area. Because of these conditions, some small-scale disturbance was induced at the north of Xinjiang along the Tianshan Mountains and the southeast wind layer was damaged temporarily, which caused strong horizontal and vertical wind shear. Because of the limitations of the detection, the spatial and temporal characteristics of the wind shear cannot be fully revealed. so it is very difficult to conduct the fine forecast. However, mesoscale numerical prediction model WRF can simulate this wind shear case ,and the results are helpful to understanding the cause of the wind shear.