广东低温阴雨的低频振荡及环流特征  

The Low Frequency Oscillation and Circulation Characteristics of Cold Rainy Weather in Guangdong

作　　者：纪忠萍[1] 高晓容 谷德军[3] 吴秀兰[1] 舒锋敏[1] 

机构地区：[1]广州中心气象台,广州510080 [2]北京市通州区气象局,北京101100 [3]中国气象局广州热带海洋气象研究所,广州510080

出　　处：《应用气象学报》2013年第1期32-42,共11页Journal of Applied Meteorological Science

基　　金：公益性行业(气象)科研专项(GYHY201006018);广东省气象局科研课题(2008B03);广东省科技计划项目(200903)

摘　　要：为了做好广东2—3月低温阴雨的中期与延伸期预报,该文分析了1953—2011年广州低温阴雨年景变化与广东低温阴雨年景变化的关系,并采用小波分析、相关分析等方法探讨了12月次年4月广州逐日气温的低频振荡及与低温阴雨的关系。结果表明:广州低温阴雨的年景变化与广东年景一致的相同率达94.9%(56/59)。轻度低温阴雨年份,12月—次年4月广州逐日气温主要存在8.0～18.3 d显著周期,而中等及严重年份主要存在10.1～28,4 d及30～89.6 d的振荡。2—3月长低温阴雨主要与18 d以上的周期振荡有关,尤其与45 d以上的季节内振荡强度变化密切相关。利用典型个例的合成分析,建立了长低温阴雨30～64 d季节内振荡的天气概念模型,它们反映了长低温阴雨回暖—降温—开始—维持—结束的大气环流演变特征,其中乌拉尔山—贝加尔湖以西的阻塞高压可作为广东出现长低温阴雨的500 hPa前兆信号。In order to predict cold rainy weather on medium-term and extended range during February--March in Guangdong, the relationship between annual prospect of cold rainy weather during 1953--2011 in Guang- dong and that in Guangzhou, and the relationship between low-frequency oscillation of Guangzhou daily temperature and cold rainy weather are analyzed from December to next April with wavelet transform and correlation analysis. The result shows that the similar ratio between the annual prospect of Guangzhou cold rainy weather and that of Guangdong is 94.9% （56/59）. In mild year of cold rainy weather, Guang- zhou daily temperature exhibits quasi-periodic oscillations of 8.0--18.3 days, 10.1--28.4 days and 30-- 89.6 days for middle and severe year, respectively. The long cold rainy weather during February--March has mainly close relationship with the intraseasonal oscillation with period more than 18 days, especially with the oscillation intensity more than 45 days. The weather concept model of long cold rainy weather with intraseasonal oscillation of 30 64 days is set up based on composite analysis of typical cases. They re- flect the evolution characteristics of atmospheric circulation of warmer--cooling--starting--maintenance-- ending period of long cold rainy weather. During warmer--cooling starting period, the blocking high in Ural Maintain and west of Baikal Lake at 500 hPa geopotential height field is maintained, the South China is controlled by straight and fluctuant westerly from weak ridge at warmer period and obvious negative a-nomalies of height field, the Mongolian High gradually enhances and moves southward in ground, and the South China is controlled by enormous cold pressure ridge from weak trough. The stronger cold air moves southwards and weak cold air continuously supplements. All of the above lead to strong temperature drop and the start of cold rainy weather. When the blocking high in Ural Mountain--west of Baikal Lake is weakened, an obvious ridge maintains, the South China is still controlled

关 键 词：低温阴雨 低频振荡 环流特征 

分 类 号：P434[天文地球—大气科学及气象学]