Study on the Causes and Evolution Characteristics of a Typical Low-Level Wind Shear in Plateau Regions
Low-altitude wind shear is a major threat to aviation flight.To study the causes and evolution characteristics of low-altitude wind shear on the plateau,the low-altitude wind shear process at Xining Airport on February 14,2022 was analyzed and studied by using laser wind radar data,airport automatic weather station data,and ERA5 reanalysis data of European Centre for Medium-Range Weather Forecasts.The results show that the downward transfer of high-altitude mo-mentum and cold air activity are the main causes of low-level wind shear during the day.During the period of high-alti-tude momentum downward transmission,the updraft and downdraft alternated,and the westerly wind of more than 16 m/s rapidly dropped from 500 m to the ground.After the strong westerly wind touched the ground,it formed a wind direction shear with the original southerly wind,and the shear gradually moved eastward and southward with the westerly wind,which affected the airport.During the period dominated by the cold air,the updraft was obvious,and the cold air flowed from the east to the south and the previous westerly wind formed an'arc'wind direction shear.With the gradual thick-ening and momentum enhancement of the East-South wind,the shear gradually advanced to the west and north,which in turn affected the airport.
万方数据
维普
