Predicted positions of tidal fronts in continental shelf of South China Sea

Based on the tidal simulation of ECOMSED, the Simpson-Hunter(S-H) stratification parameter is calculated to study the tidal fronts in the continental shelf of the South China Sea (SCS). The results show that, besides the tidal fronts around the Hainan Island which have been studied by Hu et al. (2003) [Hu, J.Y., Kawamura, H., Tang, D.L., 2003. Tidal front around the Hainan Island, northwest of the South China Sea. Journal of Geophysical Research 108(C11), 3342, doi:10.1029/2003JC001883], there are also five tidal fronts in the south of Taiwan Strait (STS), Pearl River estuary (PRE), Mekong River estuary (MRE), southwestern coast of Vietnam (SCV) and northern coast of east Malaysia (NCEM), and they are consistent with Chlorophyll-a (Chl-a) fronts detected by SeaWiFS. The positions of predicted tidal fronts in the STS and PRE are also consistent with those of sea surface temperature (SST) fronts. The criterion value of S-H, 2.6-2.7, should be used for prediction of tidal fronts in the MRE and 2.2-2.4 in the NCEM. Further studies show that tidal mixing can be considered as one of the main causes of the formation of Chl-a fronts in those five coastal sea areas, and the M2 tidal constituent plays an important role in tidal mixing in the STS, PRE, MRE and NCEM while both K1 and O1 play important roles in tidal mixing in the SCV.