Unconsolidated earth materials ranging in size from silt to boulders, which occur along a shore. Broadly defined, a beach extends from the upper landward limit of wave effects (usually the base of a sea cliff or dune) offshore to the greatest depths normally affected by wave activity (where storm waves break). Beaches of fine sand and silt-size particles normally occur where gentle wave action dominates, whereas pebbles, cobbles, and boulders are characteristic of beaches with high wave energy. Beaches can be divided into a breaker zone, surf zone, beach face, and berm (the almost horizontal area at the top). A beach is among the most dynamic of earth surface features, often changing profile on a seasonal or even daily basis.
A beach or strand is a geological formation consisting of loose rock particles such as sand, gravel, shingle, pebbles, cobble, or even shell along the shoreline of a body of water.
Components
Some geologists consider a beach to be just this shoreline feature of deposited material, but William Bascom (1980) has argued that a beach is the entire system of sand set in motion by waves to a depth of ten meters (30+ feet) or more off ocean coasts. In the Bascom approach, beaches can be viewed as either:
small systems in which the rock material moves onshore, offshore, or alongshore by the forces of waves and currents;There are several conspicuous parts to a beach, all of which relate to the processes that form and shape it. At some point the influence of the waves (even storm waves) on the material comprising the beach stops, and if the particles are small enough (that is, are sand), winds shape the feature.
The line between beach and dune is difficult to define in the field.
How beaches are formed
Beaches are deposition landforms, and are the result of wave action by which waves or currents move sand or other loose sediments of which the beach is made as these particles are held in suspension. Beach materials come from erosion of rocks offshore, as well as from headland erosion and slumping producing deposits of scree.
The shape of a beach depends on whether or not the waves are constructive or destructive, and whether the material is sand or shingle. Constructive waves move material up the beach while destructive waves move the material down the beach. On sandy beaches, the backwash of the waves removes material forming a gently sloping beach. On shingle beaches the swash is dissipated because the large particle size allows percolation, so the backwash is not very powerful, and the beach remains steep.
There are several beaches which are claimed to be the "World's longest", including Cox's Bazar, Bangladesh (120kms), Fraser Island beach, 90 Mile Beach in Australia and 90 Mile Beach in New Zealand and Long Beach, Washington (which is about 30km). Wasaga Beach, Ontario on Georgian Bay claims to have the world's longest freshwater beach.
Beaches and recreation
Beaches have long been a popular attraction for tourism and recreation. Especially popular are seaside resorts and large white sand beaches. The relatively soft formation of sand is comfortable to sit or lie on, and entering and exiting the water is far easier across a sand beach than a rocky shore. The waves present at beaches add to the enjoyment and make the sport of body surfing and related activities possible. One of the many attractions of a sand beach, especially for children, is playing with the sand, building sand castles and other constructs.
Towels and mats are typical beach "furniture".
A walk along the beach is also popular, including a long walk in the case of a long beach, for example from one seaside resort to the next. One may or may not walk with the feet in the water, and this may also alternate with the waves
In more than thirty countries in Europe, South Africa, New Zealand, Canada, South America and the Caribbean, the best recreational beaches are awarded Blue Flag status, based on such criteria as water quality and safety provision.
Due to intense use by the expanding human population, beaches are often dumping grounds for waste and litter, necessitating the use of beach cleaners and other cleanup projects.
Artificial beaches
Some beaches are artificial;
The soothing qualities of a beach and the pleasant environment offered to the beachgoer are replicated in artificial beaches, such as "beach style" pools with zero-depth entry and wave pools that recreate the natural waves pounding upon a beach. Another approach involves so-called urban beaches, a form of public park becoming common in large cities. Urban beaches attempt to mimic natural beaches with fountains that imitate surf and mask city noises, and in some cases can be used as a play park.
Beach nourishment involves pumping sand onto beaches to improve their health. Beach nourishment is common for major beach cities around the world; however the beaches that have been nourished can still appear quite natural and often many visitors are unaware of the works undertaken to support the health of the beach. IENCE is Investment to Enhance the Natural Capacity of the Environment and includes things like beach nourishment of natural beaches to enhance recreational enjoyment and snow machines that extend ski seasons for areas with an existing snow economy developed upon a natural snowy mountain.
Sounds of the beach
Beaches are noted for their sometimes serene stillness and the rhythmic sound made by waves crashing upon the sand. To experience, listen to this sound file sound recording (1.00MB) made on a
South Carolina beach at night.
Beaches as habitat
A beach is an unstable environment which exposes plants and animals to harsh conditions. Seagrasses and other beach plants grow on undisturbed areas of the beach and dunes.
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