2016年夏季中国降水的低频振荡特征及其与热带海洋大气低频振荡的联系  

The Low-frequency Oscillation Characteristics of Precipitation in China and its Relation to the Low-frequency Oscillation of Tropical Ocean in Summer 2016

作　　者：王祉苏 巩远发[1] WANG Zhisu;GONG Yuanfa(College of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610025,China)

机构地区：[1]成都信息工程大学大气科学学院,四川成都610225

出　　处：《成都信息工程大学学报》2020年第4期439-446,共8页Journal of Chengdu University of Information Technology

基　　金：国家自然科学基金资助项目(41775079);国家自然科学基金重大研究计划资助项目(91537214)。

摘　　要：针对2016年夏季长江中下游流域和东北地区降水异常偏多的现象,利用美国国家海洋大气局的逐日向外长波辐射(OLR)观测资料和中国气象局国家气象中心的逐日降水资料,采用小波分析和SVD方法,分析这两个地区降水的低频变化特征和热带海洋低频振荡与中国低频降水的关系。结果表明:(1)2016年夏季,长江中下游流域和东北区域降水都有明显的30~60 d的季节内振荡,两个地区的低频降水在夏季呈反位相变化,当长江中下游流域低频降水增多(减少)时,东北区域低频降水减少(增多)。(2)热带海洋低频OLR场与中国低频降水场SVD分析第一模态显示:受热带海洋低频对流活动的影响,当赤道以北的热带海洋和印度尼西亚地区对流活动减弱(增强)时,中国东北地区低频降水增多(减少),长江中下游流域低频降水减少(增多)。In view of the phenomenon of anomalous large precipitation in the middle and lower reaches of Yangtze river and Northeast China in the summer of 2016,based on daily outgoing longwave radiation(OLR)data from National Oce-anic and Atmospheric Administration and daily precipitation data from National Meteorological Information Center,the wavelet analysis method and the SVD method were used to analyze the characteristics of low-frequency precipitation in these two regions and the relationship between low-frequency oscillations in tropical oceans and low-frequency precipitati-on in China.The results show that:(1)In the summer of 2016,precipitation in the Yangtze River Basin and Northeast China exhibits a noticeable 30-60-day intra-seasonal oscillation feature,and low-frequency precipitation in the two re-gions presents opposite variation tendency of phase.When the low-frequency precipitation in the Yangtze River Basin shows positive(negative)anomalies,the low-frequency precipitation in the Northeast China displays negative(positive)anomalies.(2)The low-frequence OLR in tropical oceans and the first mode of SVD analysis of low-frequency SVD in China show that;when the convective activities in the tropical oceans north of the equator and the convective activities in Indonesia are weakened(intensified),low-frequency precipitation in Northeast China increases(decreases),and low-frequency precipitation in the Yangtze River Basin decreases(increases).

关 键 词：气象学 气象与气候 低频振荡 夏季降水 热带海洋 对流活动 长江中下游 

分 类 号：P461[天文地球—大气科学及气象学]