| 摘要: |
| 本文通过分析RAMA印度洋观测浮标系统锚系ADCP 实测资料, 对赤道中印度洋上层海流季节变化进行了研究。研究结果表明, 0°, 80.5°E 纬向流垂向剖面呈现上150m 层一致的东向流, 而经向流在100m 以浅呈现表层向北次表层向南的翻转流结构。赤道中印度洋上层纬向流季节信号被半年周期的东向射流Wyrtki Jets(WJs)所控制。WJs 发生于季风方向转换的季节, 4—5 月份较弱, 10—11月份较强。赤道中印度洋上层经向流年周期信号显著。北半球夏季与冬季分别出现风应力旋度驱动的Sverdrup 南向流与北向流。本文结论为赤道中印度洋上层环流季节变化特征的研究提供了观测角度的支持。 |
| 关键词: 赤道中印度洋 上层环流 Wyrtki Jets |
| DOI：10.11693/hyhz20140500128 |
| 分类号: |
| 基金项目:国家自然科学基金项目,41276011号;教育部科学技术研究项目,113041A号。 |
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| THE STRUCTURE AND SEASONAL VARIATION OF UPPER-LAYER CURRENTS AT CENTRAL EQUATORIAL INDIAN OCEAN |
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WANG Yi1,2, CUI Feng-Juan1
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1.College of Physical and Environmental Oceanography, Ocean University of China, Qingdao 266100, China;2.Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle 98115, USA
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| Abstract: |
| The ADCP current data at 0°, 80.5°E from the Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction (RAMA) program are analyzed. The annual mean state and seasonal cycle of currents at the central equatorial Indian Ocean are presented with strong observational evidence. The annual mean zonal currents in the upper 150m are eastward while the meridional currents northward at surface and southward at subsurface constituting a shallow roll at 0°, 80.5°E. The seasonal cycle of the zonal currents are dominated by the semi-annual eastward currents known as Wyrtki Jets (WJs). WJs occur in April to May and October to July. The boreal fall jets are stronger than the spring ones. Annual signal of the meridional currents is significant in the upper ocean. Southward Sverdrup currents are driven by negative curl of the sea surface wind stress in boreal summer and conversely northward Sverdrup currents occurs in boreal winter. |
| Key words: Central Equatorial Indian Ocean upper layer currents Wyrtki Jets |
