作　　者： ; ; ; ; ;

机构地区： 广州市气象局

出　　处： 《气象》 2013年第4期410-417,共8页

摘　　要： 利用华南地区多普勒天气雷达资料、气象站监测资料以及NCEP客观分析资料,分析了2012年2月27日华南地区发生的一次罕见高架对流天气过程特点。结果表明,在低层强大冷气团控制下,地面冷锋后华南地区出现的伴有短时强降水、雷电和冰雹的强对流天气过程是一次较典型的冷区"高架雷暴",近地面大气层结较稳定,低空存在逆温,强对流天气落区与850 hPa切变线位置有较好对应。中高层的西风槽东南移和高空急流南压,配合低层850 hPa南岭山脉南侧偏南急流显著加强,为高架对流发生发展提供了有利的大气环流背景。边界层冷空气补充南下迫使低层暖湿空气抬升,中高层槽前辐散气流产生高空"抽吸"作用,配合华南上空有利的大气动力和热力不稳定条件,形成了此次罕见的高架强对流。与一般地面发展雷暴不同,此次"高架雷暴"暖湿空气是从逆温以上的850 hPa附近开始对流抬升,而不是从边界层开始。 South China （SC） suffered a rarely seen elevated thunderstorm on 27 February 2012. Based on meteorological observation data, Doppler weather radar data and NCEP/NCAR analysis data, the charac- teristics and causes of the elevated thunderstorm are analyzed. The results show that this convective weather with short-time heavy rain, hail and thunderstorm which occurred behind a cold front was a typi- cal elevated thunderstorm. There was a low-level temperature inversion over SC, the atmospheric layer near surface was stable and the location of the convective weather was correlated well with the 850 hPa shear line. The east-southward propagation of westerly trough and the southward movement of westerly jet in the mid-high level together with reinforce of the 850 hPa low-level moist southerly on the southern side of the Nanling Mountains created favorable atmospheric circulation conditions for development of the elevated convection. The conditional symmetric instability of the air over SC and the convective uplift mechanism o{ warm air including southward movement of cold air in boundary layer and upper-level diver- gence contributed to the ＂elevated convection＂ weather. Different from the general thunderstorm that de- velops from the surface, the warm and moist air for this elevated thunderstorm began to lift convectively from the layer near 850 hPa which was above the temperature inversion, not beginning from the boundary layer.

关 键 词： 高架雷暴 冷锋 逆温 切变线 条件对称不稳定

领　　域： [天文地球]