南海海啸反问题预报模式

Tsunami forecasting based on inversion model in the South China Sea

通过COMCOT海啸模型计算南海马尼拉海沟潜在震源区单元板块单位滑动产生的海啸波在区域内传播过程,将计算结果组成相应南海海啸波数据库。采用浮标监测数据与数据库结合通过最小二乘法构建南海海啸预报模式。以假想马尼拉海沟发生8.3级地震海啸为案例,应用预报模式对华南地区进行海啸预测,采用30 min和60 min监测数据分别反演计算,在三个近岸验证点的波高和正问题结果比较误差分别在25%和17%之内,到达时间及相位基本一致,预报的计算时间在2 min以内。

The COMCOT model was applied to simulate the tsunami propagation generated by each of the sub-faults in Manila trench by a unit slip and the results were stored as a tsunami database for the South China Sea.The inversion model for tsunami forecasting was developed using the method of least squares by combining the real-time measurements at buoys and the precomputed database.One hypothetical event of earthquake with Mw8.3 of epicenter in Manila Trench was studied to test the model.The results show that,the forecasting matches well with the results calculated by COMCOT directly in the relatively deep water along the coastal.The errors of predicted wave heights are less than 25% and 17% using the first 0.5h and 1.0h records,respectively,and the arriving time and tsunami period matches very well.The time for the forecast calculation is within 2 minutes.