【摘要】 利用绝热、无摩擦大气湿位涡守恒理论和常规的地面观测资料、NCEP再分析资料(水平分辨率1°×1°),对山东省西北部2012年7月30日-8月1日的一次持续性暴雨过程的湿位涡场进行了诊断和分析。结果表明,这是一次副高边缘低涡切变类暴雨天气过程,500 hPa副热带高压和地面倒槽的稳定为鲁西北地区产生持续性暴雨提供了必要的环流条件;暴雨产生在θe线陡立密集区附近,θe线陡立密集区附近对流稳定度较小,有利于倾斜涡度发展;暴雨的发生发展与湿位涡的时空演变有很好的对应关系,湿位涡"正负区叠加"的配置是低涡暴雨发展的有利形势,暴雨区位于850 hPa上MPV1和MPV2的正负值过渡的零值区附近。更多还原

【Abstract】 Based on the theory of moist potential vorticity,the routine surface observational data and NCEP reanalysis data with the horizontal resolution 1° ×1°,this paper made a diagnostic analysis on a persistant rainstorm in the Northwest of Shandong Province during July 30-August 1,2012.The result showed that the persistant rainstorm mainly resulted from the low vortex at the edge of subtropical high,steady subtropical high and inverted surface trough is the advantage to the rainstorm.The rainstorm occurred in the neighbourhood of the stiff and dense section of the moist isentropes,where the convective stability was so small that it is benificial to SVD.The spatial and temporal variations of moist potential vorticity can give good indication of the development of vortex rainstorm.It is advantage to the development of vortex rainstorm that plus positive zone just over minus one.The rainstorm area is located near the transition zone of positive value and negative value of MPV1 and MPV2 at 850 hPa.更多还原