摘要: |
基于AVISO卫星高度计数据,采用小波分析和EOF分析方法,对1993—2015年东中国海海平面高度的时空变化进行分析,结合海水温度比容效应和ENSO过程探讨了海平面高度变化成因。东中国海海平面高度具有明显的季节变化,冬春季较低,夏秋季较高,且SSH极值滞后海水温度极值月份一个月出现。东中国海海平面高度整体为北低南高,由于海区水深和水文动力过程的影响,不同季节SSH空间分布区域性强。在23年间,海平面高度平均线性上升速率为2.82mm/a,具有1a、2.2a的特征变化周期。EOF分析三个主要模态依次反映了海水温度比容效应的季节变化、水动力过程的季节变化和ENSO事件的年际变化对东中国海海平面高度的影响。 |
关键词: 海平面高度 东中国海 季节变化 EOF分析 ENSO |
DOI:10.11693/hyhz20170500129 |
分类号:P731 |
基金项目:国家重点研发计划项目,2016YFA0601301号;中国科学院战略性先导科技专项项目,XDA11020305号;国家自然科学基金项目,41376006号。 |
附件 |
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TEMPORAL AND SPATIAL VARIATION OF SEA LEVEL OF THE EAST CHINA SEA |
YANG Yang, SUN Qun, YANG Min, LV Wen-Jin
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Tianjin University of Science & Technology, Tianjin 300457, China
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Abstract: |
Based on AVISO satellite altitude data, temporal and spatial patterns of the sea surface height (SSH) in the East China Sea (ECS) from 1993 to 2015 were analyzed using wavelet analysis and EOF methods. The variations of SSH related to the thermosteric effect and the ENSO were discussed. The SSH of the ECS had a significant seasonal variation, lower in winter-spring and higher in summer-autumn.The peak values of SSH lagged behind that of the sea temperature for a month. In overall, the SSH in the northern part is lower than that in the southern part of the ECS. In addition, the SSH showed obvious regional and seasonal features due to the effect of depth and ocean dynamical processes. The annual mean growth rate of SSH in the ECS from 1992 to 2015 is 2.82mm/a. Wavelet analysis results show a cycles of 1a and 2.2a in sealevel change. The first three modes of EOF (empirical orthogonal function) show that the seasonal variation of thermosteric effect and dynamical processes, and the interannual variation of ENSO had important impacts on the variations of SSH in the ECS. |
Key words: sea surface height East China Sea seasonal variation EOF analysis ENSO |