摘要
利用全球海洋模型GOCTM,采用全球无结构三角形网格,避免开边界条件引入带来的误差,采用德国AWI研究所提供的海啸源作为初始水位场,加入潮汐的水位和流场,通过潮汐模块,模拟2004年12月26日海啸发生时潮汐场下海啸波的传播。模拟结果与无潮汐加入时海啸波传播模拟结果以及印度沿岸潮位站数据进行了对比,结果显示:潮汐的加入对于海啸波到达近岸的时间和波形影响不大,但是潮汐影响着海啸波的水位分布,尤其是孟加拉湾及安达曼海域由于受到涨潮的影响,水位比无潮汐加入的情况下在同一时刻明显增加。海啸波在近岸的水位随着不同的潮汐时刻而改变,尤其是涨潮过程中增强了海啸波在近岸的水位,从而可能影响水位在陆地的爬升,给海啸的预报和预警带来不确定因素。
Based on a global ocean model GOCTM, a tsunami numerical model with tides is built up to simulate the tsunami event generated by the great Sumatra-Andaman earthquake on 26 December 2004. GOCTM takes advantage of the geometric flexibility of unstructured triangular. Meanwhile, no open boundary condition is considered in GOCTM that avoids the uncertainties to the simulation. In order to simulate the tsunami with the tide, equilibrium tide module is open. Using the tsunami source as the initial surface elevation condition which is provided by Alfred Wegener Institute （AWl） in Germany, when the tide is set up, the elevation and velocity of the tide at some time are added to the initial conditions. In order to check the result, we compare model results with tide gauge data from all around the Indian Ocean, to model results without tide. The results show that when the tsunami under the effect of the tide, the arrival time and wave form are not affected by the tide except sea surface elevation along the coast which is depending on tidal phase, especially in the Bay of Bengal and Andaman Sea because of the rising tidal effect, the elevation is increased obviously compared with the case without tidal effect at the same time. When the tsunami under the effect of the tide, the sea surface elevation along the coast are affected by the tidal phase, particularly the rising tide increases tsunami wave along the coast. This result would affect the run-up on the land and bring the uncertainty to the forecast and warning of the tsunami.
出处
《海洋预报》
2017年第1期1-8,共8页
Marine Forecasts
基金
国家重点研发计划(2016YFC1401800
2016YFC1402000
2016YFC1401400)
国家自然科学基金(41406011
41430963)
国家软科学研究计划(ZLY2015140)
中国科学院战略性先导科技专项(XDA11010201)
中央高校基本科研业务费(201564014)
