Abstract
Near-inertial oscillation is an important physical process transferring surface wind energy into deep ocean. We investigated the near-inertial kinetic energy (NIKE) variability using acoustic Doppler current profiler measurements from a mooring array deployed in the tropical western Pacific Ocean along 130°E at 8.5°N, 11°N, 12.6°N, 15°N, and 17.5°N from September 2015 to January 2018. Spatial features, decay timescales, and significant seasonal variability of the observed NIKE were described. At the mooring sites of 17.5°N, 15°N, and 12.6°N, the NIKE peaks occurred in boreal autumn and the NIKE troughs were observed in boreal spring. By contrast, the NIKE at 11°N and 8.5°N showed peaks in winter and troughs in summer. Tropical cyclones and strong wind events played an important role in the emergence of high-NIKE events and explained the seasonality and latitudinal characteristics of the observed NIKE.
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Data Availability Statement
The SMAP salinity data are produced by Remote Sensing Systems and sponsored by the NASA Ocean Salinity Science Team and available at www.remss.com. The ERDDAP wind stress data can be found at https://coastwatch.pfeg.noaa.gov/erddap/index.html. The mooring data are available at the NPOCE website (http://npoce.org.cn).
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Acknowledgment
We thank all the scientists, engineers, and crews from the R/V Kexue who deployed the mooring array and collected the ADCP data from the moorings. We are grateful to CHEN Gengxin for his valuable comments. Comments and suggestions from the two anonymous reviewers are of much help.
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Supported by the National Natural Science Foundation of China (Nos. 41776018–91858101), the Key Research Program of Frontier Sciences, CAS (No. QYZDB, SSW-SYS023), the CAS-CSIRO Project Fund (No. 133244KYSB20190031), the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB01000000) to HU Shijian, the National Program on Global Change and Air-Sea Interaction (No. GASI-IPOVAI-04), and the National Natural Science Foundation of China (No. 41976009) to LIU Lingling
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Hu, S., Liu, L., Guan, C. et al. Dynamic features of near-inertial oscillations in the Northwestern Pacific derived from mooring observations from 2015 to 2018. J. Ocean. Limnol. 38, 1092–1107 (2020). https://doi.org/10.1007/s00343-020-9332-1
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DOI: https://doi.org/10.1007/s00343-020-9332-1