东海海啸反问题预报模式研究——以日本“3·11”海啸为例

Study on inversion forecasting model for East China Sea——A case study of Japan “3·11” tsunami

采用COMCOT数值模式,将日本东海岸划分为18个单位震源,建立了日本东海岸海啸数据库并用非负约束的最小二乘法建立反问题预报模式。将本模式应用于日本"3·11"海啸,计算所得的海啸初始水位有10 m的抬高与3 m的降低,与前人研究结果基本一致,预报的浮标水位与实测资料符合良好。对比浙江省近岸潮位站实测海啸波高,预报值与实测值偏差较大。若采用反问题反演的震源,通过COMCOT非线性模式求解近岸水位,可以大幅提高预报精度。

The Japan＇s east coast was divided into 18 unit source to set up a tsunami database by using COMCOT numerical model. An inversion forecasting model was established by using least non-negative square method based on the database. The model was applied to 2011 Tohoku tsuami, the initial tsunami water level with 10m increase and 3m decrease calculated by the model was basically the same as previous research, the buoy level of prediction is in good agreement with measured data. Comparing with tsunami heights measured by tidal stations at coastal area of Zhejiang Province, the deviation of forecasted and measured value is large. But the prediction accuracy.can be greatly improved by solving COMCOT nonlinear equations with source parameters inversed by the forecasting model.