利用WAVEWATCH和SWAN嵌套计算珠江口附近海域的风浪场*

基于CCMP(Cross Calibrated Multi-platform)卫星遥感海面风场数据，通过将WAVEWATCH和SWAN (Simulating WAves Nearshore)模型嵌套的方法，数值模拟了珠江口附近海域的风浪场。将总计10个月的数值模拟的有效波高、波周期和波向分别与相应的观测值进行了定量比较。结果说明，有效波高的平均绝对误差为15.4cm，分散系数SI为0.240，相关系数为0.925；波周期的平均绝对误差为1.9s，分散系数SI为0.433，相关系数为0.636；波向的平均绝对误差为23.9°。计算的波高和波向与观测结果的变化趋势相吻合。由于第三代海浪模式本身的缺陷，导致所计算的波周期偏小。总体说来，本文所采用的数值模式能较好地模拟珠江口附近海域的风浪场。另外，还设计了6个算例以探讨采用不同的计算方法和风场对计算结果精度的影响。结果表明使用本文的数值方法和高精度的CCMP风场确实可以提高计算结果的精度。

Simulating wind wave field near the Pearl River Estuary with SWAN nested in WAVEWATCH

Based on the cross calibrated multi-platform (CCMP), a remotely-sensed sea-surface wind field by NASA, wind wave field near the Pearl River Estuary is simulated with Simulating WAves Nearshore (SWAN) nested in WAVEWATCH. The numerical results of significant wave height, wave period and wave direction are compared with the measured data quantitatively. We find that for significant wave height, the mean absolute error is 15.4 cm, Scatter Index (SI) is 0.240 and the correlation coefficient is 0.925; that for wave period, the mean absolute error is 1.9 s, SI is 0.433 and the correlation coefficient is 0.636; and that for wave direction, the mean absolute error is 23.9°. Therefore, the numerical results are in agreement with the measured wave height and wave direction. However, due to the drawbacks of the third generation wave models, the calculated wave period is shorter than the measured period. Generally, the numerical model used in this paper can simulate the wave field near the Pearl River Estuary effectively. In addition, the influences of different calculation methods and different wind fields on the precision of the numerical results and on the calculation efficiency are studied using six cases. It is illustrated that the present calculation method and the CCMP wind field can effectively improve the numerical results.