On the near-inertial variations of meridional overturning circulation in the South China Sea

• Main Authors: J. Xiao, Q. Xie, D. Wang, L. Yang, Y. Shu, C. Liu, J. Chen, J. Yao, G. Chen
• Format: Article
• Language: English
• Published: Copernicus Publications 2016-03-01
• Series: Ocean Science
• Online Access: http://www.ocean-sci.net/12/335/2016/os-12-335-2016.pdf

We examine near-inertial variability of the meridional overturning circulation in the South China Sea (SCSMOC) using a global 1 / 12° ocean reanalysis. Based on wavelet analysis and power spectrum, we suggest that deep SCSMOC has a significant near-inertial band. The maximum amplitude of the near-inertial signal in the SCSMOC is nearly 4 Sv. The spatial structure of the signal features regularly alternating counterclockwise and clockwise overturning cells. It is also found that the near-inertial signal of SCSMOC mainly originates from the region near the Luzon Strait and propagates equatorward at a speed of 1–3 m s⁻¹. Further analyses suggest that the near-inertial signal in the SCSMOC is triggered by high-frequency wind variability near the Luzon Strait, where geostrophic shear always exists due to Kuroshio intrusion.