新疆铁路沿线最强风区大风特征对比分析

利用2015-2018年新疆境内兰新铁路沿线32个大风监测站逐小时风速资料，基于统计学方法、空间分析法，从平均大风日数、大风历时、不同风速的贡献率以及平均风速不同时间尺度和地域分布的变化特征等，对兰新铁路新疆段内两个最强风区带——百里风区和前百里风区的大风特征进行统计和对比分析。结果表明：较之百里风区，前百里风区更易出现极端大风天气（大于11级风），同时具有风速"昼弱夜强"、地域分布差异性大、主导风向与兰新铁路运行方向基本垂直以致横风强劲等特点。该分析结果能够有效弥补前百里风区这一无人区气象规律探索的空白，可为探明特殊地域强风区大风最新变化规律、关键区的大风逐小时内精细化预报、专项试验研究、风速灾害预警阈值的制定等提供基础。

Comparative analysis of the gale characteristics in the strongest wind area along Lanzhou-Xinjiang railway

Based on the hourly wind speed data of 32 monitoring stations along Lanzhou-Xinjiang railway from 2015 to 2018, the gale characteristics in the two strongest wind region of Lanzhou-Xinjiang railway i.e.the 100-kilometer wind area and the pre-hundred kilometer wind area were comparatively analyzed through investigating the average number of gale days, duration of gale, the contribution rate of different wind speed, and the variation of time scales and geographical distribution of strong wind by means of statistical methods and spatial analysis.The results show that the extreme gale whose rank is greater than 11 is more likely to occur in the pre-hundred kilometer wind zone than in the hundred kilometer wind zone, which indicates some characteristics in the pre-hundred kilometer wind area under the influence of its downstream terrain relative to in hundred kilometer wind area.Specifically, in the pre-hundred kilometer wind area, the mean hourly wind speed is bigger in the nighttime (20:00 to 08:00 the following day) than in the daytime (08:00 to 20:00), and its variability in spatial distribution is larger, and the dominant wind direction is basically perpendicular to Lanzhou-Xinjiang railway, which leads to strong transversal wind.This paper can fill in the gaps of exploration of weather patterns in the pre-hundred kilometer wind area, and provide the basis for the analysis of change rules of gale in special regions, the fine forecast of hourly gale in the key regions, special experimental study and the determination of the warning threshold of wind-induced disaster.