Based on the wind field data from FNL reanalysis data, the atmospheric wind field of the height range of 0.8-47 km above Taiyuan (112.35oE, 37.37oN) is investigated. The vertical distribution characteristics and wind shear characteristics are analysed by the method of vector averaging and mathematical statistics. The wind field over Taiyuan is investigated for its effects on aircraft launch, leading to a classification of four periods based on wind characteristics: April, May and June are the early rainy season, July and August are the rainy season, September and October are the late rainy season, and November, December and January to March are the winter. According to the seasonal variation of the wind field, the vertical structure is divided into three layers with two height layers of 5 and 20 km. Below 20 km, the average wind speed in the rainy season is lower than in the other three periods. Above 20 km, the wind speeds in the winter and rainy season are higher than that in the early and late rainy season. The wind shear characteristics are calculated using the integrated vector wind method. The intensity of wind shear is greatest in the height range of 40-47 km in winter, and the maximum intensity value occurs around 12 km in other periods. The primary influence range of the wind shear caused by the maximum wind is within ±8 km. By using the new λ-PDF polynomial chaotic expansion method, the wind field parameters are effectively fitted and the uncertainty of the wind field distribution is resolved, providing theoretical support for complex flight problems.