The roles of different mechanisms related to the tide-induced fronts in the Yellow Sea in summer
- 116 Downloads
In summer, the Yellow Sea Cold Water Mass (YSCWM) is a stable water mass of low temperature lying at the bottom of the central Yellow Sea (YS). It is fringed by some typical tidal fronts, which separate deep, stratified water on the offshore side from the well-mixed, shallow water on the inshore side. Three striking fronts—Subei Bank Front (SBF), Shandong Peninsula Front (SPF), and Mokpo Front (MKF; a front off the southwestern tip of the Korean Peninsula)—have been identified by various studies from both satellite observations and model results. Tide plays an important role in the formation and maintenance of these fronts. However, it is still a matter of debate as to the roles these two kinds of mechanisms of upwelling and tidal mixing play, and how importance they are in the maintenance processes of the above three fronts. Basing a nested high-resolution model HYCOM (the Hybrid Coordinate Ocean Model), this study focuses on the different mechanisms of tidal effects on the thermal fronts in the YS in summertime. Through comparative experiments with and without tidal forcing, the results indicate that the MKF is mainly driven by tide-induced upwelling. For the SPF, tidal mixing is the dominant factor, when lower cold water is stirred upwards along the sloping topography of the western YS. Meanwhile, the combined effect of upwelling and tidal mixing is the main cause of the formation of the SBF. Diagnostic analysis of thermal balance shows that horizontal nonlinear advection induced by strong tidal currents also contributes to the thermal balance of frontal areas.
Key wordstidal front tide-induced upwelling tidal mixing thermal balance
Unable to display preview. Download preview PDF.
- Antonov, J. I., R. Locarnini, T. Boyer, A. Mishonov, H. Garcia, and S. Levitus, 2006: World Ocean Atlas 2005, Vol. 2: Salinity. NOAA Atlas NESDIS 62, U.S. Government Printing Office, Washington, D.C., 182 pp.Google Scholar
- Fang, G. H., Y. G. Wang, Z. X. Wei, B. H. Choi, X. Y. Wang, and J. Wang, 2004: Empirical cotidal charts of the Bohai, Yellow, and East China Seas from 10 years of TOPEX/Poseidon altimetry. J. Geophys. Res., 109, doi:10.1029/2004JC002484.Google Scholar
- Hu, D. X., M. C. Cui, Y. X. Li, and T. D. Qu, 1991: On the Yellow Sea cold water mass-related circulation. Yellow Sea Research, 4, 79–88. (in Chinese)Google Scholar
- Locarnini, R. A., A. Mishonov, J. Antonov, T. Boyer, H. Garcia, and S. Levitus, 2006: World Ocean Atlas 2005, Vol. 1: Temperature. NOAA Atlas NESDIS 61, US Government Printing Office, Washington, DC, 182 pp.Google Scholar
- Moon, J. H., N. Hirose, and J. H. Yoon, 2009: Comparison of wind and tidal contributions to seasonal circulation of the Yellow Sea. J. Geophys. Res., 114, C8, doi:10.1029/2009JC005314.Google Scholar
- Su, J., and D. J. Huang, 1995: On the current field associated with the Yellow Sea ColdWater Mass. Oceanologia et Limnologia Sinica, 26(S1), 1–7. (in Chinese)Google Scholar
- Xia, C. S., F. L. Qiao, Y. Z. Yang, J. Ma, and Y. L. Yuan, 2006: Three-dimensional structure of the summertime circulation in the Yellow Sea from a wave-tide-circulation coupled model. J. Geophys. Res., 111, 2156–2202.Google Scholar
- Xia, Z. W., and B. H. Guo, 1983: The cold water and upwelling in the tip areas of Shandong peninsula and Liaodong peninsula. Journal of Oceanography of Huanghai & Bohai Seas, 1, 13–19. (in Chinese)Google Scholar
- Zhao, B., 1987: A preliminary study of continental shelf fronts in the western part of Southern Huanghai Sea and circulation structure in the front region of the Huanghai cold water mass (HCWM). Oceanologia et Limnologia Sinica, 3, 159–170. (in Chinese)Google Scholar
- Zou, E. M., B. H. Guo, Y. X. Tang, J.-H. Lee, and H.-J. Lie, 2001: An analysis of summer hydrographic features and circulation in the southern Yellow Sea and the northern East China Sea. Oceanologia et Limnologia Sinica, 32, 340–348. (in Chinese)Google Scholar