冬季北太平洋流场异常主要模态与PDO及NPGO的关系  

Relationshipbetween the main modes of circulation anomalies and the PDO,NPGO modes in the North Pacific duringwinter

作　　者：吕庆平[1,2] 卢姁[2,3] 朱娟[2] 戴文灏 张铭[2] 

机构地区：[1]解放军东海舰队司令部海洋水文气象中心 [2]解放军理工大学气象海洋学院大气环流与短期气候预测实验室 [3]解放军61741部队

出　　处：《海洋学研究》2015年第2期1-7,共7页Journal of Marine Sciences

基　　金：国家重点基础研究发展计划项目资助(2013CB956203)

摘　　要：采用复经验正交函数(EOF)分解和小波分析,对冬季北太平洋上层海流异常进行了统计动力诊断,并讨论了主要模态与北太平洋年代际振荡(PDO)模态和北太平洋环流振荡(NPGO)模态的关系。结果显示,冬季北太平洋上层洋流异常复EOF分解的第一模态是PDO在流场异常上的反映,第二模态则包含了NPGO的明显信息。主要依据有:(1)第一和第二模态的实时间系数序列分别有准20a和准13a的年代际变化周期,与PDO和NPGO模态的年代际变化周期相同;(2)第一和第二模态实时间系数与北太平洋海表面温度异常(SSTA)的回归系数场的空间分布分别与PDO和NPGO模态的空间结构相近。根据第一和第二模态上层洋流异常计算得到的垂直运动异常的分布,与SSTA的PDO和NPGO模态的空间分布类似,表明海盆尺度流场异常造成的垂直运动是形成PDO和NPGO模态的重要原因。CEOF and wavelet methods were employed to discuss the relationship between the main modes of upper circulation anomalistic field in the North Pacific during winter and the PDO,NPGO modes.The results show that the first and second CEOF modes of the upper circulation anomalies are the reflection of the PDO and NPGO modes on the circulation field.Firstly,the real time coefficients of the first two modes have obvious decadal periods of about 20 and 13 years,respectively,which are the same as the periods of PDO and NPGO modes.Secondly,the regression fields of the first two time coefficients with the SSTA in the North Pacific are quite similar to the spatial feature of PDO and NPGO modes.The distributions of dynamic anomalies of near-surface temperature obtained by the vertical movement of the first two modes of the upper circulation anomalies are similar to those of PDO and NPGO modes.This means that the vertical movement of oceanic flow is the important reason of formation of PDO and NPGO modes.

关 键 词：北太平洋 流场异常 复EOF分解 PDO NPGO 

分 类 号：P732.6[天文地球—海洋科学]