太平洋海温场不同时间尺度背景下华南前汛期持续性暴雨的统计特征  

Statistical characteristics of persistent heavy rainfall during the first rainy season in South China under the background of Pacific sea temperature fields on different time scales

作　　者：王彦明 高建芸[3] 池艳珍[3] 唐振飞[3] 陈思[3] 

机构地区：[1]厦门市气象服务中心,福建厦门361012 [2]海峡气象开放实验室,福建厦门361012 [3]福建省气候中心,福建福州350001

出　　处：《大气科学学报》2015年第1期126-131,共6页Transactions of Atmospheric Sciences

基　　金：福建省科技厅科技计划重点项目(2011Y0008);公益性行业(气象)科研专项(201306067);福建省气象局开放式基金课题(2013K02);福建省气象局新录用研究生基层专项(2010G07)

摘　　要：利用1961—2012年华南逐日降水资料,分析了太平洋海温场两种不同时间尺度背景下华南前汛期持续性暴雨的统计特征,并探讨了海洋外强迫信号可能对华南前汛期降水的低频变化周期造成的影响,以期为华南前汛期持续性暴雨过程的延伸期预报提供依据。结果表明:PDO(Pacific Decadal Oscillation,太平洋年代际振荡)冷位相年,华南前汛期发生典型持续性暴雨过程的概率比PDO暖位相年大,且暴雨强度偏强,持续时间偏长;太平洋海温场两种不同时间尺度背景下,华南典型持续性暴雨过程呈现不同的特征,PDO冷位相配合冬春Nino区海温异常,华南前汛期易出现强度较强、持续时间较长的典型持续性暴雨过程;太平洋海温两种不同时间尺度的外强迫信号可能影响华南前汛期降水的低频变化周期,进而影响华南前汛期持续性暴雨的持续时间和强度。Using the observational daily precipitation data in South China during 1961—2012,this paper analyzes statistical characteristics of persistent heavy rainfall during the first rainy season in South China under the background of Pacific sea temperature fields on different time scales,and discusses the responses of low frequency cycle of precipitation during the first rainy season in South China to different sea surface temperature forcing,which can promote the development of extended-range forecast of the persistent heavy rainfall. Results show that there are higher occurring probability,stronger intensity and longer duration for the typical persistent heavy rainfall in the PDO（ Pacific Decadal Oscillation） cold phase years than in the PDO warm phase years. Under the background of Pacific sea temperature fields on different time scales,the characteristics of the persistent heavy rainfall are different. During the PDO cold phase years combined with significant sea surface temperature anomalies in Nino region in winter and spring,the persistent heavy rainfall are stronger and longer. The external forcing of Pacific sea surface temperaturefields on different time scales might have relationships with the low frequency cycles of precipitations during the first rainy season in South China,and further affect intensity and duration of the persistent heavy rainfall.

关 键 词：华南前汛期 持续性暴雨 太平洋年代际振荡(PDO) Nino区海面温度 

分 类 号：P426.6[天文地球—大气科学及气象学]