东南沿海台风风暴潮增水过程中非线性机制和地形的作用研究: 以1509号台风"灿鸿"为例

Based on FVCOM (Finite Volume Community Ocean Model), we constructed a numerical model covering the Bohai Sea, Yellow Sea, and the East China Sea. NCEP data were used to drive the model to simulate the storm surge generated by typhoon Chan-hom. The model was calibrated by in-situ observations of water level at total gauge stations. Based on this model, the nonlinear terms and topographical effects on the modelling of storm surges were studied. The tide-surge interaction during storm surge process was analyzed. The results show that the tide-surge interaction can suppress the storm surge at the climax of astronomical tide and help the growth of storm surge at the ebb of astronomical tide. M₂ tide, S₂ tide, and K₁ tide were added respectively to analyze the influence of amplitude and period of tide on the nonlinear reaction. The results indicate that the higher the height of tide is, the more obvious the nonlinear effect is. The nonlinear reaction of semidiurnal tide is more significant than that of the diurnal tide. In addition, the semidiurnal fluctuation which appeared near the peak-value time was also related to the tide-surge interaction. According to the numerical results, the topography also has a certain impact on storm surge. The steeper the slope is, the lower the peak water level is. The existence of the Ryukyu Islands reduced the area of storm surge on the southeast coast, but expanded the area of high value of storm surge.