| 摘要: |
| 使用 EOF 分析与相关分析等高级统计方法, 对近 30 年来日本海热容海平面的年际变化进行了研究, 期间(1976年 1月—2005年 12月)日本海热容海平面异常 TSLA与 SOI存在较强的负相关, 整个日本海的区域平均热容海平面异常 TSLA 与 SOI 的相关系数为?0.54, SOI 超前热容海平面异常 3至 5 个月。日本海热容海平面异常 EOF 第一模态的空间分布显示, 日本海热容海平面在东南部海域的变化幅度明显强于西北部海域; 相关分析表明, 东南日本海的区域平均热容海平面异常TSLA响应SOI 较快, 与 SOI 的相关性更强, 其相关系数达?0.57, SOI 超前热容海平面异常 1 个月左右。计算还表明, 日本海的热通量异常 HFA 比日本海热容海平面异常 TSLA 超前 2 至 3 个月, 二者存在正相关, 相关系数达 0.54。这说明, 日本海的热通量带来(或者带走)的热量对日本海的热容海平面上升(或者下降)做出了显著的贡献。进一步的研究表明, SOI 与日本海热通量异常 HFA 之间存在相对较弱的负相关, 相关系数为?0.43, SOI 超前 HFA 1 个月左右。这表明, 日本海的热通量异常 HFA 受到 ENSO循环的调制。由此可知, 日本海热容海平面对 ENSO 有较好的响应: 当厄尔尼诺事件发生时, SOI 是负值, 由于 SOI 与 HFA 负相关, 因此, HFA 为正值; 与此同时, HFA 与 TSLA 正相关, TSLA 为正值。 综上所述, 近 30 年全球的 ENSO 循环对日本海热容海平面异常 TSLA 有反位相的调制。
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| 关键词: 热容海平面, 厄尔尼诺, 南方涛动, EOF 分析, 热通量 |
| DOI：10.11693/hyhz201004022022 |
| 分类号: |
| 基金项目:国家重点基础研究发展计划 973 项目,973-2007CB411807 号。 |
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| INTERANNUAL VARIABILITY OF THE THERMOSTERIC SEA LEVEL IN THE JAPAN/EAST SEA AND ITS RESPONSE TO El Ni?o AND SOUTHERN OSCILLATION OVER THE LAST 30-YEAR |
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WANG Tian-Shun1,2, LIU Yu-Guang1, RONG Zeng-Rui1
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1.Physical Oceanography Laboratory, Ocean University of China;2.College of Mathematics and Physics, Qingdao University of Science & Technology
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| Abstract: |
| The interannual variability of the thermosteric sea level anomalies (TSLA) was investigated in the Japan/East Sea (JES) over the last 30 years (1976—2005) , by using statistical correlation analysis and EOF analysis.There existed a strong negative correlation between the region-averaged thermosteric sea level anomalies (TSLA) in the JES and southern oscillation index (SOI); and the maximum correlation coefficient is ?0.54, with the SOI preceding about four months, which indicates that interannual variability of the thermosteric sea level anomalies (TSLA) is closely related to ENSO. The positive TSLA occurred simultaneously with the development of El Ni?o events, whereas the states during La Ni?a events were opposite to those during El Ni?o events. The spatial patterns of the first EOF mode of the TSLA in the JES showed that there existed larger amplitude in the southeastern JES than that in the northwestern JES. Statistical correlation analysis indicated that there existed a stronger correlation between the region-averaged thermosteric sea level anomalies (TSLA) in the southeastern JES and SOI; and TSLA in the southeastern JES had more rapid response on SOI, the correlation coefficient reaching ?0.57 with the SOI preceding about one month. The correlation coefficient is 0.54 with the heat flux anomalies (HFA) preceding the TSLA in the JES about two months. This suggested that the heat flux flowing into (or flowing out of) the JES should make significant contribution to the rise (or fall) of thermosteric sea level. There existed a strong negative correlation between the heat flux anomalies (HFA) in the JES and SOI during the ENSO warm phase (1976—2006), which indicated that the HFA was closely influenced by ENSO event.
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| Key words: rmosteric sea level anomalies, El Ni?o, Southern Oscillation, EOF analysis, Heat flux anomalies |
