A new objective tsunami magnitude scale

Abstract

Tsunami research has suffered considerably due to the lack of an objective magnitude scale. The Imamura‐Iida Grade Scale, although it has been used until now as a magnitude scale, is not objective, and it is more appropriate to call it a tsunami intensity scale. The tsunami magnitude scale proposed by Abe (1979) is also based on coastal tide gauge records, and this is not truly an objective magnitude scale. A new magnitude scale is proposed here, based on total tsunami energy, and it is demonstrated that this new scale will provide an adequate representation of the whole spectrum of tsunamis, starting from the negligible ones and including those that have devastated whole coastlines.