Tsunamis have been a significant threat to humans living in coastal regions throughout recorded history. The recent tsunami of September 29, 2009 was a tragic reminder of this fact, as the waves caused over 180 deaths on the islands of Samoa, American Samoa, and Apia in the south Pacific. Recent modeling results and observations have demonstrated that the ionospheric signature of an ocean tsuna...

Stromboli is one of the most active volcanoes in the Aeolian island arc in south Tyrrhenian sea, Italy. In the last 100 years the most relevant volcanic eruptions have been accompanied by local tsunamis, that have caused damage and casualties. In some cases the direct mechanism of local tsunami generation is clear, i.e. pyroclastic flows entering the sea. In some others it is uncertain and some...

We investigate the generation, propagation, and probabilistic hazard of tsunami spawned by oceanic asteroid impacts. The process first links the depth and diameter of parabolic impact cavities to asteroid density, radius, and impact velocity by means of elementary energy arguments and crater scaling rules. Then, linear tsunami theory illustrates how these transient cavities evolve into vertical...

Numerical model simulations, combined with tide-gauge and satellite altimetry data, reveal that wave amplitudes, directionality, and global propagation patterns of the 26 December 2004 Sumatra tsunami were primarily determined by the orientation and intensity of the offshore seismic line source and subsequently by the trapping effect of mid-ocean ridge topographic waveguides.

Two major earthquakes near the Central Kuril Islands (Mw=8.3 on 15 November 2006 and Mw=8.1 on 13 January 2007) generated trans-oceanic tsunamis recorded over the entire Pacific Ocean. The strongest oscillations, exceeding several meters, occurred near the source region of the Kuril Islands. Tide gauge records for both tsunamis have been thoroughly examined and numerical models of the events ha...

Numerical simulations were generated to investigate the propagation processes of distant tsunamis, using a set wave equations based on variational principle considering both strong nonlinearity and dispersion waves. First, we proposed estimate formulae for time variations tsunami height wavelength first tsunami, by assuming that initial profile was long crest in uniform bathymetry. Second, cons...

Tsunamis generated by earthquakes involve physical processes of different temporal and spatial scales that extend across the ocean to the shore. This paper presents a shock-capturing dispersive wave model in the spherical coordinate system for basin-wide evolution and coastal run-up of tsunamis and discusses the implementation of a two-way grid-nesting scheme to describe the wave dynamics at re...

In Japan, Japan Meteorological Agency, JMA, has the official responsibility for the public for tsunami forecasts and issuance of tsunami information. For the tsunami forecast the first step is precise and prompt estimation of the location and magnitude of the earthquake because generation of tsunami is strongly controlled by the focal depth and the magnitude of the earthquake. In case that the ...