Describe how wind waves travel in groups. What will be an ideal response?

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Progressing groups of swell with the same origin and wavelength are called wave trains. The
leading waves in the wave train are drained of energy because they must begin the circular
movement of the undisturbed water into which they are intruding. These leading waves
gradually disappear, but after the wave train has passed, some energy remains behind in the
circles to form new waves. New waves thus form behind as the leading waves disappear at
the front of the wave train. Though each individual wave moves forward with a speed
proportional to its wavelength in deep water, the wave train itself moves forward at only half
that speed. Groups of waves therefore move ahead at half the speed of individual waves
within the group. The half-speed advance of the wave train is called group velocity and is the
speed with which wave energy advances. Individual waves do not persist in the ocean.
Individual waves last only as long as they take to pass through the group. Only deep-water
waves are subject to dispersion. As deep-water waves move into shallow water, the speed of
individual waves within the group slows until wave speed equals group velocity.