The variation approach to travel-time calculations on regular grids

Application of the variation method to simulate tsunami wave rays and to estimate the wave travel times corresponding is studied. In some cases, the wave ray determined by this method, connecting two points of the water area, may not present the global extreme, which provides the shortest tsunami travel time. In this way, for the correct calculation of the wave travel time from one point to another a broken line passing through the nodes of the calculation grid, which is built by the method based on the Huygens principle must be taken as an initial approximation. The variation method described can be applied to optimize the grid method for the wave travel time determination.