Sea waves are formed due to continuous motion of water combined with the gravitational forces of the sun and the moon, and the blowing winds. The article describes different types of sea waves.
How Sea Waves are formed?
When the wind is blowing on the sea, the surface exerts the gravitational force on the bottom layer of the wind. This, in turn, exerts the pull on the layer above it until it reaches the top-most layer. With the gravitational pull being different at each layer, the wind moves at a different speed. The top-most layer tumbles, forming a circular motion. This creates a downward pressure at the front and upward pressure at the rear of the surface, causing a wave.
Types of Sea Waves
The waves of the sea are categorized based on their formation and behavior. Here are the different types of waves of the sea:
Breaking Waves – Formed when the wave collapses on top of itself. They are of two types:
- Plunging Breaker – The wave reaches a steeper beach and curls, moving over a pocket of air. It travels very fast.
- Spilling Breaker – The wave reaches a sloping sandy beach, dispersing the energy over a large area.
Deep Water Waves/Swell Waves – Are made up of a number of waves of different lengths superimposed on each other. They are straight and long, powerful, and travel great distance.
Destructive/Plunging Waves – High waves of short wavelength and a vertical ellipsis. When the wave breaks on a steep beach, the water plunges forward into the trough. They have a powerful backwash and drag objects into the sea.
Inshore Waves – The length of these waves is less than the depth of the water they enter, which decreases the velocity of the waves. This results in the decrease of the wavelength and increase in the height, eventually breaking the wave. These waves drain the beach as a backwash.
Internal Waves – Formed due to the disturbances found between two water masses of different density. They are high and become turbulent currents when they hit a landmass.
Kelvin Waves – Formed due to lack of winds in the Pacific Ocean. They are high and wide waves, warmer than the surrounding water.
Progressive Waves – Move with a steady speed, so they are called Progressive Waves. They are of two types:
- Capillary Waves – Formed when wind creates pressure over Capillarity, the binding force that holds the water molecules of the ocean surface together.
- Orbital Progressive Waves – Formed at the boundary of two liquids with different density.
Refracted Waves – Travel in shallow water when they approach the shore. The shallowness decreases the power of the wave and causes a curve. These are usually seen near headlands and bays.
Seiche Waves – Caused due to the movement within a confined space. These have long wavelengths and rarely result in any damage as their height is generally few inches.
Shallow Water Waves – Move in shallow waters at a depth less than 1/20th of their wavelength. They are of two kinds:
- Tidal Waves – Formed due to the gravitational pull of the sun and the moon on the ocean.
- Seismic Sea Waves/Tsunami – Caused due to earthquakes beneath the ocean. They are also called as Tsunami. They travel extremely fast in open water, have significant height in shallow water, and are very dangerous and devastating.
Spilling Waves/Constructive Waves – Have long wave length and low height. When they reach the shore, the ellipse becomes horizontal. When the wave breaks, the water reaches the upper part of the beach with little backwash.
Swell Waves/Surging Waves – Intense waves generating from the center of a storm where the winds are strong. These expel little energy, travel long distance, and break on distant shores.
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