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利用WRF模式对2009年7月29日的一次高原低涡个例进行数值模拟,研究了凝结潜热加热及其与对流活动的反馈在高原低涡发生发展过程中的作用及影响机制.通过模拟结果与实况资料的对比分析,发现WRF模式能够较好地模拟此次低涡的移动路径、中心强度和降水场分布.不考虑凝结潜热加热效应的敏感性试验结果中,模式模拟的低涡移动迟滞,降水量减少,并在移动至高原中部后迅速减弱消失.进一步分析高原低涡的结构发现,凝结潜热加热使得低涡中心附近的上升运动延伸至高层,并产生较强的对流活动,而更为深厚的上升运动又释放出较多的潜热,从而形成一种正反馈机制.位涡收支诊断分析表明,低层凝结潜热加热垂直梯度项产生的正位涡变化有利于高原低涡的增强与东移,位涡垂直通量散度项与凝结潜热加热垂直梯度项引起的位涡变化趋势相反.在高原低涡的形成和发展阶段,由于凝结潜热加热与对流活动间的正反馈机制,潜热加热垂直梯度项引起的正位涡增强,凝结潜热加热对低层的位涡变化起主要作用,有利于高原低涡的增强与东移;低涡进入成熟阶段后,凝结潜热的贡献减小,位涡水平通量散度项与位涡垂直通量散度项对位涡的变化起主要作用.“,”The influence of latent heating and its feedback effect on a Qinghai-Tibetan Plateau vortex occurring on 29 July 2009 was examined by using the WRF model in this study.Two experiments were conducted.In the control experiment,all physical processes were retained.In the sensitivity experiment,latent heat released by large-scale and cumulus convective precipitation was removed,while other physical processes were kept.By comparing model results and reanalysis data,it is found that the model can simulate the vortex moving path,intensity and the vortex-induced precipitation well in the control experiment.Without taking the latent heating into account,the simulated vortex moves quite slowly and disappear in the middle of the plateau,with little precipitation.The comparison of these two numerical simulations demonstrates that there is a positive feedback mechanism between the latent heating and the convection.The latent heating leads to intensive convective activity,and the convection extends to the upper level,thus much latent heat releases to the atmosphere.The potential vortices diagnostic analysis shows that,in low level,positive potential vorticity (PV) tendency caused by the vertical gradient of latent heating is beneficial to the strengthening and migrating of the plateau vortex.The PV tendency generated by vertical flux divergence term is contrary to that caused by vertical gradient of latent heating.In the development period of plateau vortex,because of the positive feedback mechanism between the latent heating and the convection,the positive PV tendency generated by the vertical gradient of latent heating increases rapidly,and the latent heating plays a leading role in the PV change at low levels.When the vortex develops into mature period,the contribution of latent heating decreases and divergence terms play important roles.