Previously reported (Loomis, 1974) was the scheme of composing a tsunami by convoluting the source function with a family of previously calculated responses to unit impulse functions, which had been specified as initial conditions at points in the source region. A new application of an old idea makes this scheme considerably more useful. Namely, that the Green's function for the linear, oceanwide hydrodynamic equation is reciprocal in its space coordinates. The response atAdue to a unit impulse atBis exactly the same as the response atBdue to a unit impulse atA.This means that for a prediction at pointAit is necessary only to put a unit impulse atAtime‐step the resulting disturbance throughout the ocean, and record the time history of the water level at each grid point in the ocean. This generates all of the Green's functions needed for any source area for a future tsunami prediction scheme at pointA.These prerecorded functions are the Green's functions, and are available for simulating any tsunami at pointAfrom any source region.
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机译:先前报道(Loomis,1974)是通过将源函数与一系列先前计算的对单位脉冲函数的响应相结合来组成海啸的方案,这些响应已被指定为源区域各点的初始条件。旧想法的新应用使该方案更加有用。也就是说,线性海洋流体动力学方程的格林函数在其空间坐标中是倒数的。单位脉冲 atBis 的响应 atAdue 与单位脉冲 atA 的响应 atB. 完全相同,这意味着对于 pointAit 的预测,只需要将单位脉冲 atA 时间步进整个海洋产生的扰动,并记录海洋中每个网格点的水位时间历史。这些预先记录的函数是绿函数,可用于模拟任何源区域的任何海啸,用于模拟任何源区域的海啸。
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