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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Acknowledgment
The mooring near Mindanao coast was deployed and recovered by the Institute of Oceanology, Chinese Academy of Sciences during the cruise of the R/V Science 1 or R/V Science in 2010–2014. The author thanks the crews, technicians, and all participants on the all of these cruises. Comments and suggestions from two anonymous reviewers are gratefully appreciated.
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Supported by the National Natural Science Foundation of China (Nos. 41576014, 41976011) and the National Key Research and Development Program of China (No. 2017YFA0604102)
Data Availability Statement
The mooring data used in this study are available from the corresponding author on reasonable request. The HYCOM data and WOA13 for this paper are available respectively from the Asian-Pacific Data-Research Center (http://tds.hycom.org/thredds/dodsC/GLBa0.08/) and National Oceanographic Data Center (NODC) (https://www.nodc.noaa.gov/OC5/woa13).
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Wang, Q. The identified 30–50-day variation in the subthermocline current east of Mindanao. J. Ocean. Limnol. 38, 1354–1367 (2020). https://doi.org/10.1007/s00343-020-0021-x
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DOI: https://doi.org/10.1007/s00343-020-0021-x