NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-13-2863-2013 A wavefront orientation method for precise numerical determination of tsunami travel time Fine I. V. 1 Thomson R. E. 1 Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, British Columbia, Canada 15 11 2013 13 11 2863 2870 Copyright: © 2013 I. V. Fine 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/13/2863/2013/nhess-13-2863-2013.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/13/2863/2013/nhess-13-2863-2013.pdf

We present a highly accurate and computationally efficient method (herein, the "wavefront orientation method") for determining the travel time of oceanic tsunamis. Based on Huygens' Principle, the method uses an eight-point grid-point pattern and the most recent information on the orientation of the advancing wavefront to determine the time for a tsunami to travel to a specific oceanic location. The method is shown to provide improved accuracy and reduced anisotropy compared with the conventional multiple grid-point method presently in widespread use.

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