基于非地转干 Q 矢量（QD）分解方法，结合 ERA5 再分析资料和中国气象局热带气旋最佳路径资料，诊断分析了 1981-2022年近海北上热带气旋（Tropical Cyclone，TC）造成上海沿岸水域大风的成因。结果表明：（1）影响风力越大，垂直上升运动越强，强上升中心高度越低，垂直上升运动层次越厚，TC的影响风力与其环流内的垂直运动关系密切；（2）大风影响期间，QD矢量散度辐合区的范围和强度与垂直上升运动区对应，垂直上升运动中心与QD矢量散度辐合中心基本一致，且垂直上升运动越强，QD矢量散度辐合越强，表明 TC 大风影响区域内的垂直上升运动与 QD 矢量散度辐合场有很好的对应关系；（3）将 QD矢量沿等位温线分解得到 QD s 和 QD n，分别反映大尺度和中尺度的天气系统信息，结果表明：在大风影响期间，QD s 和QD n 矢量散度辐合强度随影响风力的增大而增强，相同风级的QD n 矢量散度辐合强度均强于QD s 矢量，且影响风力越大，QD n 矢量散度辐合强度与QD s 矢量之间的差异越大，10级风区域可比7级风区域大两个量级，表明中尺度天气系统的强迫作用可能是造成TC大风的主要原因。本研究结果对TC大风的预报有较好的指导意义和业务应用价值。

Based on the ageostrophic dry Q vector（QD）partitioning method，combining with the ERA5 reanalysis data and the China Meteorological Administration（CMA）tropical cyclone best track data，the causes of off‐ shore northward tropical cyclone（TC）gales in the coastal areas of Shanghai from 1981 to 2022 are diagnosed and analyzed， The results show that：（1）the stronger the wind force，the stronger the vertical upward motion， the lower the height of the strong updraft center and the thicker the vertical upward motion layer，which means the TC wind is closely related to the vertical motion within its circulation；（2）the range and intensity of the QD vector divergence convergence area are correspond to the vertical upward motion zone during the gale process. The vertical upward motion center coincides with the QD vector divergence convergence center. The stronger the vertical updraft is，the stronger the convergence intensity of the QD vector divergence，which indicates that there is a good correspondence between the vertical upward motion in the area affected by the TC gales and the convergence zone of the QD vector divergence；（3）the results of the QD vector partitioning method show that during the period of TC gale，the convergence intensity of QD s and QD n vector divergence increases with the wind scale. For the same wind level，the convergence intensity of the QD n vector divergence is stronger than that of the QD s vector divergence. Furthermore，the higher the wind scale is，the more distinct the difference between the convergence intensity of the QD n and QD s vector divergence. In details，the different convergence intensity in the scale 10 wind region can be larger than the scale 7 wind region by two orders of magnitude，suggesting that the forcing of the mesoscale weather system is the main cause of the TC gales. The results of this study provide valuable guidance and have significant practical application value for the forecasting of TC gales.