8 Conclusion
Wind wave investigations in the World's oceans are carried out by scientists in many countries. Now it is a subject of international research. This
is manifested by a great number of papers and monographs (Komen et al.,
1994; Problems of Research and Mathematical Modeling of Wind Sea. 1995;
Massel, 1996; Young, 1999), published in the last few years and devoted
to the study of wind waves and numerical simulation. The present monograph is a logical continuation of those publications. The main attention is
paid to investigation of the effect of spatial inhomogeneous media on wind
waves, including the effect of the Earth's surface sphericity, the presence of
non-uniform currents, uneven bottom, ice cover, etc, which affect wind wave
spectral structure formation in the World's oceans.
The principal conclusions are as follows.
1. In order to investigate the influence ofthe inhomogeneity of the World's
oceans on wind waves the general problem formulation is stated based on
principal physical notions. The problem is reduced to solving the kinetic
equation on a spherical surface, considering the main wave-forming factors:
wave energy input, non-linear energy transfer in the wave spectrum, energy
dissipation due to wave breaking and bottom friction, wave transformation
in non-uniform currents, shallow water and ice cover.
Taking into account the solution difficulties, an approach based on the
analysis of spatial and temporal variability scales of the natural phenomenon,
is suggested. The scale estimation of different physical mechanisms forming the wind wave spectral structure simplifies the solution and reveals the
most effective mechanisms for every separate case. It should be noted that at
the same time the geometric aspect of the solution is analysed (this means
a description of wave packet propagation in phase space) and described not
only by the right, but also by the left-hand side of the kinetic balance equation.
2. Great attention is paid in the monograph to the description of wave
evolution in a non-uniform current. Both wind wave generation and wave
transformation are affected by currents. The latter not only cause essential
spectrum and wave parameter variations (the wave height can sometimes be
changed in a countercurrent), non-uniform currents can result in generating
freak waves in the ocean, whose catastrophic effects on oceanic vessels are
notoriously known.
Wind wave investigations in the World's oceans are carried out by scientists in many countries. Now it is a subject of international research. This
is manifested by a great number of papers and monographs (Komen et al.,
1994; Problems of Research and Mathematical Modeling of Wind Sea. 1995;
Massel, 1996; Young, 1999), published in the last few years and devoted
to the study of wind waves and numerical simulation. The present monograph is a logical continuation of those publications. The main attention is
paid to investigation of the effect of spatial inhomogeneous media on wind
waves, including the effect of the Earth's surface sphericity, the presence of
non-uniform currents, uneven bottom, ice cover, etc, which affect wind wave
spectral structure formation in the World's oceans.
The principal conclusions are as follows.
1. In order to investigate the influence ofthe inhomogeneity of the World's
oceans on wind waves the general problem formulation is stated based on
principal physical notions. The problem is reduced to solving the kinetic
equation on a spherical surface, considering the main wave-forming factors:
wave energy input, non-linear energy transfer in the wave spectrum, energy
dissipation due to wave breaking and bottom friction, wave transformation
in non-uniform currents, shallow water and ice cover.
Taking into account the solution difficulties, an approach based on the
analysis of spatial and temporal variability scales of the natural phenomenon,
is suggested. The scale estimation of different physical mechanisms forming the wind wave spectral structure simplifies the solution and reveals the
most effective mechanisms for every separate case. It should be noted that at
the same time the geometric aspect of the solution is analysed (this means
a description of wave packet propagation in phase space) and described not
only by the right, but also by the left-hand side of the kinetic balance equation.
2. Great attention is paid in the monograph to the description of wave
evolution in a non-uniform current. Both wind wave generation and wave
transformation are affected by currents. The latter not only cause essential
spectrum and wave parameter variations (the wave height can sometimes be
changed in a countercurrent), non-uniform currents can result in generating
freak waves in the ocean, whose catastrophic effects on oceanic vessels are
notoriously known.