Abstract
The daily regional reanalysis product of the China Ocean Reanalysis (CORA) product was released in website in 2018. Using in situ observational data including Argo profiling floats, drifters, and cruise data, the performance of CORA in the South China Sea in terms of temperature, salinity, current and mixed layer depths is evaluated based on timescale (seasonal and interannual) and spatial distribution characteristics. The CORA temperature, salinity, and mixed layer depth show certain seasonal and interannual variations. In 50–400 m depth in the SCS, the CORA temperature is colder in winter and warmer in summer and autumn. In 0–150 m in the SCS, the CORA salinity is higher in most time of the year. However, in the second half of the year, the salinity is slightly weaker in 100–150 m depth. In most years, the CORA mixed layer depths tend to be shallower, and in season, shallower in winter and deeper in summer. In spatial distribution, the closer the area is to the coast, the greater the CORA errors would be. The CORA temperature is colder in the western side and warmer in the eastern side, resulting in a weaker SCS western boundary current (SCSwbc). In most areas, the CORA mixed layer depths are shallower. In the area close to the coast, the CORA mixed layer depths change rapidly, and the deviations in the mixed layer depths are larger. In the central SCS, the CORA mixed layer depths change slowly, and the deviations in the mixed layer depths are also small.
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Data Availability Statement
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
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Acknowledgment
We are grateful to the National Marine Data and Information Service of China (NMDIS) for developing, maintaining and making available (http://cora.nmdis.org.cn/) the CORA datasets that were used in this study. Argo data are from the China Argo Real-time Data Center (ftp://ftp.argo.org.cn/pub/ARGO/global/). Drifter data are from the National Oceanic and Atmospheric Administration Atlantic Oceanographic and Meteorological Laboratory Physical Oceanography Division (https://www.aoml.noaa.gov/phod/gdp/index.php). We thank the crew of research vessels (Experiment No. 1 & Experiment No. 3) and all participants in the cruise for their efforts in field work.
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Supported by the National Key R&D Program of China (No. 2018YFC1406202) and the National Natural Science Foundation of China (No. 41976188).
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Fan, M., Wang, H., Zhang, W. et al. Evaluation of the China Ocean Reanalysis (CORA) in the South China Sea. J. Ocean. Limnol. 38, 1640–1653 (2020). https://doi.org/10.1007/s00343-019-9146-1
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DOI: https://doi.org/10.1007/s00343-019-9146-1