基于SWAN模型的东沙岛海域有效波高模拟与分析

Simulation and Analysis of Significant Wave Height over Seas of Dongsha Island Based on SWAN Model

基于加密的不规则三角形网格,利用SWAN模型分别在开启和关闭底摩擦耗散项下模拟东沙岛海域有效波高,同时将0.038m^2s^(-3)和0.067m^2s^(-3)两种底摩擦系数模拟的有效波高与TOPEX/Poseidon卫星观测值进行对比。结果表明,运用这两种底摩擦系数均能很好地模拟东沙岛海域的有效波高,其中采用底摩擦系数0.038m^2s^(-3)模拟效果会更好,精度会更高。采用0.038m^2s^(-3)底摩擦系数的底摩擦耗散主要对东沙岛东北部小于100m的水深地区起作用,耗散强度随着水深的变深而减少。

Based on encrypted irregular triangular grids,the significant wave heights over seas of Dongsha Island with activated or de-activated bottom friction dissipation were simulated by using the SWAN model.The bottom friction coefficients 0.038m^2s^-3 and 0.067m^2s^-3 of JONSWAP were adopted respectively.Compared with TOPEX/Poseidon altimetry data,the results show that although the significant wave heights can be well simulated with both the two friction coefficients,the simulated result with the bottom friction coefficient of 0.038m^2s^-3 is better than that with the bottom friction coefficient of 0.067m^2s^-3.The bottom friction dissipation with the bottom friction coefficient of 0.038m^2s^-3 can give its effects on waves mainly in the northeast area of Dongsha Island with its water depth less than 100 m,and the dissipation intensity becomes weak as the water depth increases.