Author(s): Damien Violeau
Linked Author(s): Damien Violeau
Keywords: Tsunamis; Asteroid fall; Extreme events
Abstract: The question of ‘cosmogenic’ tsunamis, i.e. tsunamis determined by the fall of an asteroid in the ocean, is difficult to address. It might sounds odd to investigate such a question, but there is a need for probabilistic assessment of very rare extreme maritime and coastal events in some industrial contexts, such as in nuclear safety for the sake of power plants protection against coastal floods. A complete methodology for addressing this issue was proposed by Ward and Asphaug (2000). Here we use their methodology, along with more recent data regarding the asteroid rate of fall on the Earth, their falling velocity, etc., and make some simplifying assumptions to obtain analytical, simple formulae giving the return interval of a cosmogenic tsunami as a function of the maximum wave height of interest. We apply this method to the European Atlantic coasts and find that a wave of 1m would occur about every 100,000 years. As a comparison, such a return interval corresponds to a storm surge of about 3m on the same coasts, in average. Reference Ward, S.N., Asphaug, E. (2000), Asteroid Impact Tsunami: A Probabilistic Hazard Assessment, Icarus 145:64–78.