| 摘要: |
| 利用小波分析方法, 对热带太平洋( 30?S—30?N, 130?E—80?W) 1992 年10 月3 日—1996 年10 月9 日期间的海平面高度资料从振荡周期、强度和传播等方面进行了全面分析。研究结果表明, 海平面高度存在明显的年变化、58—139 天振荡和29—35 天振荡。其中年变化主要存在于0?—15?N、135?E—95?W, 传播不明显。58—139 天振荡主要位于以20?N 和20?S为中心的两个副热带区域中( 范围约为16?N—30?N、130?E—150?W 和17?S—30?S、150?E—150?W) , 它们向西传播, 传播速度随纬度增高而变慢, 在20?N 传播速度约为10cm/s, 波长约为800km。90 天左右的振荡具有年变化且与El Nino 事件有很好的对应关系。29—35 天振荡主要存在于中东太平洋以5?N 和5?S 为中心的带状区域中, 经度范围约为160?W—105?W 和170?W—140?W, 传播不明显。年变化、58—139 天和29—35 天振荡方差占总方差的百分比分别约为: 20%—40%、10%和1%—2%。 |
| 关键词: 热带太平洋, 海平面高度, 小波分析 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目, 49776286 号 |
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| ANNUAL AND INTRASEASONAL VARIATIONS IN SEA SURFACE HEIGHT OVER THE TROPICAL PACIFIC |
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HU Rui-Jin, LIU Qin-Yu
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College of Physical and Environmental Oceanography , Ocean University of Qingdao
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| Abstract: |
| On the basis of wavelet theory, comprehensive analysis of the data of sea surface height (TOPEX/Posidon data) in the tropical Pacific ( 30?S—30?N, 130?E—80?W) , focusing on oscillation period, strength and propagation, is undertaken. The main results obtained are as follows. (1) Distinct variations with periods of one year, 58—139 days and 29—35 days exist in the surface height data. (2) Annual variation in the Northern Hemisphere locates in 0?N—15?N, with longitudinal extension of 170?E—90?W in 0?N—5?N and 130?E—90?W in 5?N—15?N, whereas in the Southern Hemisphere a narrow band extending from 0?N, 175?E to 30?S, 100?W can be seen. Oscillation of 58—139 day periods is remarked in 16?N—30?N, 130?E—155?W and 17?S—30?S, 150?E—150?W, where there are two subtropical regions with central latitude of 20?N and 20?S, respectively. 29—35 day variations are found in two bands in the central and eastern Pacific centered by 5?N and 5?S, ranging from 160?W to 105?W and from 170?W to 140?W, respectively. (3) Oscillation of 58—139 day periods propagates westward, with speed decreasing with latitude. The speed of propagation and the wavelength are around 10cm/s and 800km, respectively. Annual variations and oscillations of 29—35 days have no obvious propagation features. (4) Oscillation of 90 days period or so reveals annual variability and has a good correlation with ENSO. (5) The ratios of variances for period of one year, 58—139 days and 29—35 days to total variance are about 20% —40%, 10% and 1%—2% , respectively. |
| Key words: Tropical Pacific, Sea surface height,Wavelet analysis |
