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The vertical wave propagation in an inhomogeneous compressible atmosphere is studied in the framework of a linear theory. Under specific conditions imposed on atmospheric parameters, solutions can be found in the form of travelling waves with variable amplitudes and wave numbers that do not reflect in the atmosphere in spite of its strong inhomogeneity. Model representations for the sound speed have been found, for which waves can propagate in the atmosphere without reflection. A wave energy flux retains these reflectionless profiles, which confirms that energy can be transferred to high altitudes. The number of these model representations is fairly large, which makes it possible to approximate real vertical distributions of the sound speed in the Earth??s atmosphere using piecewise reflectionless profiles. The Earth??s standard atmosphere is shown to be well approximated by four reflectionless profiles with weak jumps in the sound speed gradient. It has been established that the Earth??s standard atmosphere is almost completely transparent for the considered vertical acoustic waves in a wide range of frequencies, which is confirmed by observational data and conclusions derived using numerical solutions of original equations. 相似文献
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Zaytsev A. I. Pelinovsky E. N. Yalciiner A. Susmoro H. Prasetya G. Hidayat R. Dolgikh G. I. Dolgikh S. G. Kurkin A. A. Dogan G. Zahibo N. Pronin P. I. 《Doklady Earth Sciences》2019,486(1):588-592
Doklady Earth Sciences - Numerical simulation of a tsunami from September 28, 2018, on Sulawesi Island (Indonesia) is carried out. It is shown that the observed distribution of tsunami heights... 相似文献
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In the coastal oceans, the interaction of currents (such as the barotropic tide) with topography can generate large-amplitude,
horizontally propagating internal solitary waves. These waves often occur in regions where the waveguide properties vary in
the direction of propagation. We consider the modelling of these waves by nonlinear evolution equations of the Korteweg–de
Vries type with variable coefficients, and we describe how these models are used to describe the shoaling of internal solitary
waves over the continental shelf and slope. The theories are compared with various numerical simulations. 相似文献
35.
V. A. Dubinina A. A. Kurkin E. N. Pelinovsky O. E. Poloukhina 《Izvestiya Atmospheric and Oceanic Physics》2006,42(2):254-261
Nonlinear three-wave interactions of Stokes edge waves propagating both in one direction and in opposite directions along a uniformly sloping shelf are considered. In the cases when only the lowest four modes participate in interaction, the synchronism conditions are determined and interaction coefficients are calculated. It is shown that the interaction coefficients of unidirectional edge-wave modes can vanish for certain triads. The spatiotemporal dynamics of a triad of edge waves is investigated. In addition, expressions are given for the resonance interaction coefficients of edge waves over the bottom of an arbitrary profile. 相似文献
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Doklady Earth Sciences - Cases of “freak waves” that occurred in the period from 2011 to 2018 and information on which is currently available are analyzed. In total, 210 cases of... 相似文献
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Ira Didenkulova Efim Pelinovsky Tarmo Soomere 《Pure and Applied Geophysics》2008,165(11-12):2249-2264
The problem of tsunami wave runup on a beach is discussed in the framework of the rigorous solutions of the nonlinear shallow-water theory. We present an analysis of the runup characteristics for various shapes of the incoming symmetrical solitary tsunami waves. It will be demonstrated that the extreme (maximal) wave characteristics on a beach (runup and draw-down heights, runup and draw-down velocities and breaking parameter) are weakly dependent on the shape of incident wave if the definition of the “significant” wavelength determined on the 2/3 level of the maximum height is used. The universal analytical expressions for the extreme wave characteristics are derived for the runup of the solitary pulses. They can be directly applicable for tsunami warning because in many cases the shape of the incident tsunami wave is unknown. 相似文献
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I. I. Didenkulova A. V. Sergeeva E. N. Pelinovsky S. N. Gurbatov 《Izvestiya Atmospheric and Oceanic Physics》2010,46(4):530-532
A run-up of irregular long sea waves on a beach with a constant slope is studied within the framework of the nonlinear shallow-water
theory. This problem was solved earlier for deterministic waves, both periodic and pulse ones, using the approach based on
the Legendre transform. Within this approach, it is possible to get an exact solution for the displacement of a moving shoreline
in the case of irregular-wave run-up as well. It is used to determine statistical moments of run-up characteristics. It is
shown that nonlinearity in a run-up wave does not affect the velocity moments of the shoreline motion but influences the moments
of mobile shoreline displacement. In particular, the randomness of a wave field yields an increase in the average water level
on the shore and decrease in standard deviation. The asymmetry calculated through the third moment is positive and increases
with the amplitude growth. The kurtosis calculated through the fourth moment turns out to be positive at small amplitudes
and negative at large ones. All this points to the advantage of the wave run-up on the shore as compared to a backwash at
least for small-amplitude waves, even if an incident wave is a Gaussian stationary process with a zero mean. The probability
of wave breaking during run-up and the applicability limits for the derived equations are discussed. 相似文献
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The influence of the incident wave form on the extreme (maximal) characteristics of a wave at a beach (run-up and draw-down heights, run-up and draw-down velocities, and the breaking parameter) is studied. It is suggested to use in the calculations the definition of wavelength at a level of 2/3 of the maximal height, which to a certain degree correlates with the definition of the significant wavelength accepted in oceanology. Such a definition allows us to unify the relations for extreme run-up characteristics so that the influence of the incident wave form becomes insignificant. The obtained universal relations can be used for the estimates of run-up characteristics when the exact information about the form of the incident wave is not available. 相似文献