利用河西走廊13个气象站逐时地面气象观测资料和MICAPS高低空资料，对该区2010年4月24～25日、2014年4月23～24日和2018年4月4日3次不同强度槽型沙尘暴过程垂直动量特征进行诊断分析，得到槽型沙尘暴的垂直动量传输特征，更好地为槽型沙尘暴的精细化网格预报预警提供有力技术支撑，增强大风强沙尘暴的防灾减灾能力。结果表明：300 hPa极锋急流是造成河西走廊地区槽型沙尘暴的主要高空动力系统，大风沙尘暴出现在高空偏西风急流（≥32 m/s）、中空急流（≥20 m/s）和低空急流（≥12 m/s）附近。沙尘暴前期，近地层大气干热，当高空冷空气侵入，与中低层暖空气进行剧烈交换，在边界层形成不稳定层结；高空槽后冷空气下沉（冷平流中心强度小于等于-10×10^-5 K/s），将强风迅速向下传递到地面产生大风；槽前高空急流加强垂直动力抽吸，深厚的辐合辐散区与地面冷锋增强上升运动，最大上升速度位于500 hPa，强度小于等于-30×10^-5 Pa/s。沙尘暴区距离高空急流轴中心位置越近，辐合辐散中心差值越大、垂直距离越近，辐合中心位置越低，对流性不稳定层结越厚、所处高度越低，冷平流中心强度越强，最大上升速度区与冷平流中心距离越近，沙尘暴强度越强、持续时间越长；300 hPa高空急流轴中心控制河西走廊地区的范围越广，沙尘暴出现范围越大。

Hourly surface meteorological observation data from 13 weather stations along the Hexi Corridor, China, and MICAPS high- and low-air data were used to analyze the vertical structure characteristics of trough-type strong sandstorm weather over the Hexi Corridor on April 24~25, 2010, April 23~24, 2014, and April 4, 2018. The results show that the polar front jet at 300 hPa is the main upper air dynamic system causing trough sandstorms in the Hexi Corridor area. Gale sandstorms appear near the upper-air westerly jet (≥32 m/s), hollow jet (≥20 m/s), and low-level jet (≥12 m/s). In the early stages of a sandstorm, the surface layer air is dry and hot. Then, the cold air invades, resulting in a violent exchange between the cold and warm air, which leads to the formation of an unstable layer junction in the boundary layer. The cold air sinks after the high trough (the central strength of cold current less than or equal to -10×10^-5 K/s), which rapidly transfers the strong wind down to the ground and generates strong winds. The upper-level jet in front of the trough strengthens the vertical dynamic pumping, and the deep convergence and divergence zones and the surface cold front enhance the upward movement. The maximum upward velocity was observed at 500 hPa and its intensity was less than or equal to -30×10^-5 Pa/s. The closer the sandstorm is to the center of the jet stream axis, the greater the difference in convergence and divergence centers. The closer the vertical distance, the lower the convergence center position, the thicker the convectional unstable stratification, the lower the height, the stronger the intensity of the cold advection center, and the rising speed area reaches a maximum. The nearer the cold advection is to the center distance, the stronger the sandstorm and the longer the duration. The wider the center, the more the 300 hPa upper-level jet axis controls the Hexi corridor area and the wider the sandstorm appears.