Yellow Sea And East China Sea, Suspended Material Variation Of The Study

Total surface suspended sediment concentration (SSC) data derived from the SeaWiFS ocean color remote data over the Yellow and East China Sea (YECS) from 1998 to 2002, QuikSCAT version-3a and NCEP-2 blended wind field data, the contemporaneous sea surface temperature (SST) and SeaWiFS Normalized water-leaving radiance data are used to analyze the transportation of suspended sediment in the YECS and its dynamical mechanism. The conclusions can be drawn as following.1. High density suspended sediment front in the estuaries and suspended sediment sub-front in the offshore area coincide with 10-30 mg/l and 2-4 mg/l concentration isopleths, respectively. Main eight suspended sediment front are existed in the YECS, which represent mature phase in winter, while return back and converge in a narrow nearshore region, therefore, the suspended sediment front and the sub-front can not be distinguished exactly in summer.2. The SSC in the YECS represents strongly seasonal variability, with the widest distribution in Feb and the most narrow distribution in Aug. The amplitude of high density suspended sediment front is about 3 longitude's width, while the sub-front is about 4 longitude's width. The inter-annual variability of SSC is stronger in the area affected by runoff rather than the area only affected by coastal currents in summer.3. The variation of SSC was closely related with the change of local wind speed on a seasonal scale, moreover a little time lag. There are many factors influencing the relationship between them on an intra-seasonal scale, such as currents, sediment source and water depth, but their correlation coefficients are all significant at 99%. On a seasonal scale, the variation of SSC lags the change of local wind speed in 1-2 months, while on an intra-seasonal scale, the impact of local wind speed on the SSC is significant in the shallow nearshore region where the impact of sediment source and coastal currents are little.4. In the Bohai gulf, Laizhou gulf, the southern Yellow Sea and the northern East China Sea, the trend of SSC (taken by logarithm) is opposite with the trend of SST, but in the same amplitude. This relationship can be described as that the sum of normalized value of two variables is zero. Using the relationship, the SSC between 124-128°E and 30-34°N can be estimated from the known SST data.