作　　者： (周宇）;

机构地区： 三沙市气象台,海南三沙573199

出　　处： 《海洋预报》 2017年第4期58-65,共8页

摘　　要： 对南海西沙一次冷空气引发强风天气进行分析。分析表明:高空低涡东移南下,横槽转竖,强冷空气爆发,大举南下入侵处于低纬的西沙,是引起西沙强风天气的主要环流背景。探讨850 hPa变温场分布特征指出:负变温的演变、强弱分布等与地面气压场演变特征有关,地面气压场中等压线的密集区与强风关系明显。温度平流场分布演变与地面气压梯度、变压梯度有较明显的一致性,冷平流可增强地面气压梯度和变压梯度,是西沙强风生成与发展的重要原因。 The characteristic of gale weather process accompanied by severe cold air on xisha islands of South China Sea was studied in this paper. The results showed that the circulation background was resulted from the south falling vortex, zonal trough became a meridianal one and the strong cold air breaking out aggressive invaded XiSha at low latitude. Through the discussion of the distribution characteristics of the varying temperature field at 850hPa, it pointed out the evolution and strength distributions of negative varing temperature had a relation with the surface pressure field character, and the isobar dense zone also had a significant association with gale. The distribution and evolution of temperature at advection level showed a same trend with surface pressure gradient and allobaric gradient. The cold advection could enhance surface pressure gradient and allobaric gradient, which was an important factor for the occurrence and development of gale weather process on xisha islands.

关 键 词： 强风天气 变温场 气压梯度 温度平流