Select Page Waves Waves are generated by wind blowing over the sea.
Waves are caused by the frictional drag of wind over the water - Waves of oscillation - water particles move in near-circular orbits which decrease in diameter with depth. Waves of translation - water particles actually move forward.
Description of waves - Wave crest - The highest part of a wave. Wave trough - The lowest part of a wave. Wave height - vertical distance between the trough and the crest of a wave. Wavelength - horizontal distance between the successive crests of a wave. Wave base - maximum depth to which waves move the water; equals about half of the wave length.
Effect of approaching shoreline on waves Moving water particles in a wave of oscillation cannot move up and down when they run into the bottom.
This interference of the bottom with the moving water particles forces the wave to slow down. Slowing of the wave causes shortening of the wavelength and a corresponding increase in the wave height.
Finally, as the water continues to shallow, the upper part of the wave runs away from the lower part. The wave breaks, turns into a wave of translation and washes up onto the shore. Wave refraction around headlands Waves reach shallow water sooner in front of headlands.
These waves slow down and the wavelength shortens in front of the headlands, but waves in the bays continue at the same speed and wavelength because they have not yet come into the shallow water.
Result is that the waves bend refract around the headlands Source for Diagram: Longshore currents and beach drift Oscillation waves that are breaking at an angle to the shoreline produce translation waves that move diagonally up and down the beach.
This diagonal swash and backwash on the beach creates a longshore current just offshore that moves parallel to the beach and also produces beach drift, which is transport of sand along the beach.
Swim parallel to the shore to escape a rip current. Wave erosion Waves erode and transport materials just like running water in a river does; dissolved, suspended, and bed loads are all transported in the surf zone.
Clay and silt in the suspended load are washed out to sea and are deposited offshore in the deeper parts of the ocean. Sand and gravel in the bed load are transported down the beach in the direction of the beach drift.
Wave erosion in the surf zone is by the process of abrasion, which is most active along headlands where wave energy is concentrated.
Features produced by wave erosion - Wavecut cliff - A steep cliff along the shoreline. Wavecut platform - A flat, nearly horizontal surface eroded by the waves at the low tide level.
Sea stack - An isolated, resistant rock island just offshore from the cliff or beach.
Sea arch - A tunnel eroded by the waves through an otherwise resistant rock mass.Beach Profiles 1. Beach ProfilesAS Geography ForeshoreOnce a wave breaks, its water moves as a sheet upslope as swash, and falls back toward the sea as backwash. (Draw annoted sketch)Choose either a beach or a spit. Describe the chosen landform and explain the role played by longshore drift in its formation.
Nevertheless, there are several factors that influence the erosive force of waves: Strength of wind, length of time wind blows and the fetch. Waves with a large fetch and subjected to strong winds are generally known as destructive waves.
These waves are steep and tend to break downwards onto the beach. With reference to a located example, describe and explain how a coastal environment provides opportunities for human activities. Outline two ways by which waves transport sediment.
3. Explain two ways in which coastal areas are managed to resolve possible conflicts Documents Similar To coasts past paper questions. Quiz 6 Soln (Coastal. The clothes a person wears tells us many things: their status in life, for example, or their cultural affiliation or identity.
They can tell us what era they live in, and even a person’s current state of mind or intent. Describe the processes of marine erosion and explain how these processes can influence the formation of a wave-cut platform. 4. Explain how waves can transport and deposit Sediment in coastal areas.
Jul 14, · CONSTRUCTIVE WAVES Constructive waves are low energy waves that deposit materials on a coast. As the waves approach such as coast, the friction between the waves and the sea bed causes the waves to slow down at some distance from the coast.
The waves break gently over a long distance. Swash is powerful than .