冬季热带印度洋上层流场异常模态分析

发布时间：2018-01-03 09:58

本文关键词：冬季热带印度洋上层流场异常模态分析　出处：《气候与环境研究》2017年04期 　论文类型：期刊论文

【摘要】：利用复经验正交函数(CEOF)分解对冬季热带印度洋海洋上层流场异常做了模态分析和结果讨论,得到以下主要结果:该流场异常前两个模态均呈现赤道俘获波形式,其异常在赤道上最大,向南北两侧迅速衰减,呈现纬向流的形态;第一、二模态的性质分别是大洋赤道波动的半波和1波形态,这表明此时赤道波动异常在大洋流场异常中占有重要地位。冬季第一模态大洋垂直运动所导致的近表层海温异常与春、秋季不同,此时在赤道印度洋呈现正—负—正的经向分布态势,这与印度洋耦极子(Indian Ocean Dipole,IOD)的不同,并是IOD在冬季衰亡的直接原因。第二模态相应的海温异常则在赤道东印度洋呈现北负南正的分布态势。第一模态与南亚冬季风异常密切有关,为印度洋冬季风环流模态。第一、二模态都有明显的年际变化和年代际变化,年际变化均为3~5年,主要的年代际变化则分别为约18、22年,此外两者还均有约13年的年代际变化。本文第一、二模态年代际变化的主周期也是冬季北太平洋和冬季热带太平洋流场异常第二、一模态的主周期。
[Abstract]:By using the complex empirical orthogonal function (CEOF) decomposition of winter tropical India ocean upper ocean flow anomalies do modal analysis and discussion of the results, the main results are as follows: the flow field anomaly before two modes showed the equatorial trapped waves, the largest anomalies in the equatorial south, North on both sides of the rapid decay of zonal flow patterns, showing the first, second mode is respectively; the nature of ocean equatorial waves of half wave and 1 wave form, which indicates that the abnormal fluctuations in the equatorial ocean flow anomaly plays an important role. In the first winter SST mode vertical motion caused by ocean anomalies and spring, autumn, this time at the equator in India ocean is positive - negative - positive meridional distribution situation, and the India Ocean dipole (Indian Ocean, Dipole, IOD) is different, and is IOD in the direct cause of decay in winter. The second modes of the corresponding SST anomalies in the equatorial eastern India The present distribution of North South are negative trend. The winter monsoon and South Asia anomaly is closely related to the first mode, India ocean winter monsoon circulation mode. The first, second mode has obvious interannual and interdecadal variation, interannual variation was 3~5 years, interdecadal changes mainly were respectively about 18,22 years, in addition to decadal variation there were about 13 years. The main period of the main cycle in the first, second mode the interdecadal variation of the North Pacific in winter and winter and tropical Pacific flow abnormalities in second, first modes.

【作者单位】：中国科学院大气物理研究所;中国人民解放军61741部队;
【基金】：国家重点基础研究发展计划(973计划)2013CB956203~~
【分类号】：P732
【正文快照】： 浩瀚的印度洋仅次于太平洋是世界第二大洋,位于我国的西南方,印度洋上空的大气状态及印度洋大洋状态对我国天气和气候有明显影响,特别是对我国西南地区(彭京备,2012;徐志清和范可,2014)。热带印度洋位于亚洲季风区,受南亚季风的控制,而南亚季风对我国的西南地区也有显著影响(

【参考文献】