Tsunamis Generated and Amplified by Atmospheric Pressure Waves Due to an Eruption over Seabed Topography

Abstract

Numerical simulations were generated using a nonlinear shallow-water model of velocity potential to study the fundamental processes of tsunami generation and amplification by atmospheric pressure waves. When an atmospheric pressure wave catches up with an existing tsunami that is propagating as a free wave over an abrupt change in water depth, the amplified tsunami propagates in the shallower water. An existing tsunami propagating as a free wave over a sloping seabed is also amplified by being passed by atmospheric pressure waves. When atmospheric pressure waves travel over an abrupt change in water depth, the water surface profile of tsunamis in the shallower water depends on both the interval of the atmospheric pressure waves and the phase of the tsunami-generation process over the change in water depth. Moreover, when atmospheric pressure waves travel over an abrupt change in water depth, the tsunami amplitude in the shallower water increases, as the water depth of the shallower area is decreased and the Proudman resonance is further reduced. When an atmospheric pressure wave train with positive pressure travels over a sloping seabed, the amplification of tsunami crests propagating as free waves is controlled by leaving the forced water waves following the atmospheric pressure waves. Conversely, the amplitudes of tsunami troughs propagating as free waves increase.

Two-way coupled long-wave isentropic ocean-atmosphere dynamics

“…One-way coupled models have been used to study Rissaga storms in the Balearic sea (Monserrat, Ibbetson & Thorpe 1991;Renault et al 2011;Romero, Vich & Ramis 2019), Abiki storms in Japan (Fukuzawa & Hibiya 2020;Kubota et al 2021), storms in the Adriatic sea (Denamiel et al 2019), storm resonance with tides (Williams et al 2021), continental shelf resonance (Vennell 2007;Thiebaut & Vennell 2011) and shore interactions (Chen & Niu 2018;Dogan et al 2021). Following the Tonga event, OWC models were used to simulate the generated meteotsunami along one-dimensional great-circle lines starting from Tonga (Kakinuma 2022;Sekizawa & Kohyama 2022;Tanioka, Yamanaka & Nakagaki 2022), two-dimensional (2-D) truncated regions of the globe (Heidarzadeh et al 2022;Lynett et al 2022;Pakoksung, Suppasri & Imamura 2022;Peida & Xiping 2022;Ren, Higuera & Liu 2022;Yamada et al 2022) and 2-D global simulations (Kubota, Saito & Nishida 2022;Omira et al 2022). In each of these cases, the atmospheric wave is stripped of its thermodynamic properties and acts as a rigid piston, assuming a sea-level forcing travelling at a set speed that is estimated from available observation data.…”

“…2021). Following the Tonga event, OWC models were used to simulate the generated meteotsunami along one-dimensional great-circle lines starting from Tonga (Kakinuma 2022; Sekizawa & Kohyama 2022; Tanioka, Yamanaka & Nakagaki 2022), two-dimensional (2-D) truncated regions of the globe (Heidarzadeh et al. 2022; Liu & Higuera 2022; Lynett et al.…”

A Numerical Study on the Response of a Very Large Floating Airport to Airplane Movement

“…Based on the results of the onedimensional propagation calculations [22], floating-body waves are significantly amplified when the moving speed of a point load on a floating thin plate is close to the phase velocity of the linear shallow-water waves, i.e., gh, in shallow-water conditions. This is due to resonance similar to that occurring in tsunami generation due to atmospheric-pressure waves, e.g., [39], based on the Proudman resonance [40]. Such resonance phenomena, often with a tail including waves of short wavelengths, are also known in other transient waves, e.g., [41][42][43][44][45][46].…”

Numerical Simulation of Surface and Internal Wave Excitation due to an Air Pressure Wave

“…The waveform of the air pressure wave was an isosceles triangle, where the length of its base, i.e., the wavelength λ, was 10 km or 20 km. The maximum and minimum pressures p m of positive and negative air pressure waves, respectively, were 2 hPa and −2 hPa, respectively, referring the values in the meteotsunami and eruption cases [11,21]. The position of the air pressure wave center at the initial time, i.e., t = 0 s, was x 0 = 50 km.…”

“…The excitation mechanism underlying these phenomena is the Proudman resonance [14], which is also known as the cause of other transient waves, e.g., [15,16,17,18,19]. Moreover, the resonance triggered by air pressure waves from a volcanic eruption may generate global tsunamis, e.g., [20,21]. Artificial waves can also be created by the resonance when an airplane moves on a very large floating airport [22].…”