利用1981—2020年常规探空资料对塔里木东风低空急流进行了分析。结果表明：（1） 塔里木东风低空急流平均每年出现74.2 d,整体呈减少趋势;平均风速为16.3 m·s^-1,呈减小趋势;平均高度为1555.1 m,呈升高趋势;平均高层垂直风切变为9.94×10^-3 s^-1,低层为7.33×10^-3 s^-1,均呈减弱趋势。（2） 塔里木东风低空急流的季节变化明显,其日数、风速和垂直风切变都是春季最多（强）,夏季次之,冬季最小（弱）;高度则为冬季最高、秋季次之,春季最低。（3） 塔里木东风低空急流的逐月差异较大,其日数和高层垂直风切变均在5月最多（强）,12月最少（弱）;平均风速在5月最大,12月最小;平均高度在1月最高,4月最低;低层垂直风切变在4月最强,12月最弱。（4） 塔里木东风低空急流的平均持续时间为2.3 d,夏季最长,冬季最短,出现次数随持续时间的增加而迅速减小,其中,持续1 d的塔里木东风低空急流出现次数最多,占总次数的48%;持续时间在3 d以内的出现次数占总次数的76.0%。位于内陆干旱区的塔里木东风低空急流,从上下层垂直风切变的分布特征来看,总体属于大尺度低空急流,与我国季风区的中尺度低空急流存在差异。

The low-level jet has an important effect on the occurrence and development of events such as rainstorms, sandstorms, and severe convection. We analyzed conventional sounding data from 1981 to 2020 to determine the characteristics of the low-level jet in the east wind of Tarim. Our findings reveal that, from 1981 to 2020, there was a decreasing trend in the days, mean wind speed, and vertical wind shear of the easterly low-level jet, whereas there was an increasing trend in the mean height of this jet. The easterly low-level jet in Tarim occurred on 74.2 days per year, on average. The low-level jet of the East wind appears 74.2 days per year, its annual average wind speed is 16.3 m·s^-1, and its average height is 1555.1 m. The vertical wind shear in the upper layer was 9.94×10^-3 s^-1 and that in the lower layer was 7.33×10^-3 s^-1. The number of days, wind speed, and vertical wind shear were highest in spring, followed by summer, and lowest in winter, whereas the height was greatest in winter, followed by autumn, and lowest in spring. There was a considerable monthly difference in the low-level easterly jet in Tarim; the days and vertical wind shear of the upper layer were at the maximum in May and the minimum in December. The average wind speed was at its maximum in May and its minimum in December. The average height was greatest in January and lowest in April. The vertical wind shear at the lower level was at its maximum in April and its minimum in December. The average duration of the easterly low-level jet in Tarim was 2.3 days, with the longest duration in summer and the shortest in winter. There was a rapid decline in the frequency of the easterly low-level jet as the duration increased. The most frequent easterly low-level jets were those that lasted for one day; these accounted for 48% of the total frequency. Those with a duration of less than three days accounted for 76.0% of the total. In conclusion, the easterly low-level jet in Tarim, which is located in the inland arid region, belongs to the large-scale low-level jet, which is different from the low-level jet in China’s monsoon region.