Abstract
After validated by the in-situ observation, the slab model is used to study the wind-generated near-inertial energy flux (NIEF) in the South China Sea (SCS) based on satellite-observed wind data, and its dependence on calculation methods and threshold criteria of the mixed layer depth (MLD) is investigated. Results illustrate that the total amount of NIEF in the SCS could be doubled if different threshold criteria of MLD are adopted. The NIEF calculated by the iteration and spectral solutions can lead to a discrepancy of 2.5 GW (1 GW=1×109 W). Results also indicate that the NIEF exhibits spatial and temporal variations, which are significant in the boreal autumn, and in the southern part of the SCS. Typhoons are an important generator of NIEF in the SCS, which could account for approximately 30% of the annual mean NIEF. In addition, deepening of the MLD due to strong winds could lead to a decrease of NIEF by approximately by 10%. We re-estimate the annual mean NIEF in the SCS, which is (10±4) GW and much larger than those reported in previous studies.
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Acknowledgements
Acknowledgement for the mooring data support from “National Earth System Science Data Sharing Infrastructure, National Science & Technology Infrastructure of China (http://www. geodata.cn)”; QSCAT/NCEP blended ocean winds are managed by the Data Support Section of the Computational and Information Systems Laboratory at the National Center for Atmospheric Research in Boulder, Colorado (http://rda.ucar.edu/datasets/ ds744.4/); SODA data were provided by the SODA/TAMU research group, Texas A&M University (http://soda.tamu.edu/); the best track typhoon data sets were available at http://www.jma. go.jp/jma/jma-eng/jma-center/rsmc-hp-pub-eg/besttrack.html.
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Foundation item: The National Natural Science Foundation of China under contract No. 40976016; the Basic Scientific Fund for the National Public Research Institutes of China under contract No. GY0217Q06; the National Science and Technology Major Project of the Ministry of Science and Technology of China under contract No. 2018YFF01014100; the Natural Science Foundation of Shandong Province, China under contract No. ZR2015PD009.
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Sun, B., Lian, Z., Yuan, Y. et al. Seasonal variability of the wind-generated near-inertial energy flux in the South China Sea. Acta Oceanol. Sin. 38, 136–145 (2019). https://doi.org/10.1007/s13131-018-1338-6
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DOI: https://doi.org/10.1007/s13131-018-1338-6