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Cite this paper: |
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WANG Qingye. The identified 30-50-day variation in the subthermocline current east of Mindanao[J]. Journal of Oceanology and Limnology, 2020, 38(5): 1354-1367 |
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The identified 30-50-day variation in the subthermocline current east of Mindanao |
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| WANG Qingye1,2,3 |
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1 Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;
2 Qingdao National Laboratory for Marine Science and Technology, Qingdao 266000, China;
3 Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China |
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| Abstract: |
| Based on nearly 4 year-long moored velocity measurements at 8°N/127°E and a high-resolution ocean model output, a significant 30-50-day variation in the subthermocline current east of Mindanao was identified for the first time in addition to the 60-80-day variation reported in previous studies. The 30-50-day variation is an important component and it explains considerable variance same as that of the 60-80-day variation. The 30-50-day variation is vertically coherent in the subthermocline current. The standard deviations of the 30-50-day variation in zonal and meridional directions are of comparable, and is about 4.5-5 cm/s. Eddy-tracking analysis indicated that ocean eddies originating from the North Equatorial Current (10°N-11°N) contribute to the 30-50-day and the 60-80-day variations. The 30-50-day eddies propagate faster than the 60-80-day eddies. |
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| Key words:
intraseasonal variability|subthermocline current|Mindanao
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| Received: 2020-01-15 Revised: 2020-02-12 |
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