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A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle beach, , etc., or biological sources, such as or coralline algae. Sediments settle in different densities and structures, depending on the local wave action and weather, creating different textures, colors and gradients or layers of material.
Though some beaches form on inland freshwater locations such as and , most beaches are in coastal areas where wind wave or Ocean current action deposits and reworks sediments. Coastal erosion and changing of beach geologies happens through natural processes, like wave action and Extreme weather. Where wind conditions are correct, beaches can be backed by coastal dunes which offer protection and regeneration for the beach. However, these natural forces have become more extreme due to climate change, permanently altering beaches at very rapid rates. Some estimates describe as much as 50 percent of the earth's sandy beaches disappearing by 2100 due to climate-change driven sea level rise.
Sandy beaches occupy about one third of global coastlines. These beaches are popular for recreation, playing important economic and cultural roles—often driving local Tourism industry industries. To support these uses, some beaches have human-made infrastructure, such as lifeguard posts, , showers, and bars. They may also have hospitality venues (such as resorts, camps, hotels, and restaurants) nearby or housing, both for permanent and seasonal residents.
Human forces have significantly changed beaches globally: direct impacts include bad construction practices on dunes and coastlines, while indirect human impacts include water pollution, plastic pollution and coastal erosion from sea level rise and climate change. Some coastal management practices are designed to preserve or restore natural beach processes, while some beaches are actively restored through practices like beach nourishment.
Wild beaches, also known as undeveloped or undiscovered beaches, are not developed for tourism or recreation. Preserved beaches are important biomes with important roles in aquatic or marine biodiversity, such as for breeding grounds for or nesting areas for or . Preserved beaches and their associated dune are important for protection from extreme weather for inland ecosystems and human infrastructure.
Beach may refer to:
The former are described in detail below; the larger geological units are discussed elsewhere under Shoal.
There are several conspicuous parts to a beach that relate to the processes that form and shape it. The part mostly above water (depending upon tide), and more or less actively influenced by the waves at some point in the tide, is termed the beach berm. The berm is the deposit of material comprising the active shoreline. The berm has a crest (top) and a face—the latter being the slope leading down towards the water from the crest. At the very bottom of the face, there may be a trough, and further seaward one or more long shore bars: slightly raised, underwater embankments formed where the waves first start to break.
The sand deposit may extend well inland from the berm crest, where there may be evidence of one or more older crests (the storm beach) resulting from very large storm waves and beyond the influence of the normal waves. 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 (sand size or smaller), winds shape the feature. Where wind is the force distributing the grains inland, the deposit behind the beach becomes a dune.
These geomorphic features compose what is called the beach profile. The beach profile changes seasonally due to the change in wave energy experienced during summer and winter months. In temperate areas where summer is characterised by calmer seas and longer periods between breaking wave crests, the beach profile is higher in summer. The gentle wave action during this season tends to transport sediment up the beach towards the berm where it is deposited and remains while the water recedes. Onshore winds carry it further inland forming and enhancing dunes.
Conversely, the beach profile is lower in the storm season (winter in temperate areas) due to the increased wave energy, and the shorter periods between breaking wave crests. Higher energy waves breaking in quick succession tend to mobilise sediment from the shallows, keeping it in suspension where it is prone to be carried along the beach by longshore currents, or carried out to sea to form longshore bars, especially if the longshore current meets an outflow from a river or flooding stream. The removal of sediment from the beach berm and dune thus decreases the beach profile.
If storms coincide with unusually high tides, or with a freak wave event such as a tidal surge or tsunami which causes significant coastal flooding, substantial quantities of material may be eroded from the coastal plain or dunes behind the berm by receding water. This flow may alter the shape of the coastline, enlarge the mouths of rivers and create new deltas at the mouths of streams that had not been powerful enough to overcome longshore movement of sediment.
The line between beach and dune is difficult to define in the field. Over any significant period of time, sediment is always being exchanged between them. The drift line (the high point of material deposited by waves) is one potential demarcation. This would be the point at which significant wind movement of sand could occur, since the normal waves do not wet the sand beyond this area. However, the drift line is likely to move inland under assault by storm waves.Blair and Dawn Witherington (2007), Florida's Living Beaches, A Guide for the Curious Beachcomber, (Pineapple Press)
The composition of the beach depends upon the nature and quantity of sediments upstream of the beach, and the speed of flow and turbidity of water and wind. Sediments are moved by moving water and wind according to their particle size and state of compaction. Particles tend to settle and compact in still water. Once compacted, they are more resistant to erosion. Established vegetation (especially species with complex network root systems) will resist erosion by slowing the fluid flow at the surface layer. When affected by moving water or wind, particles that are eroded and held in suspension will increase the erosive power of the fluid that holds them by increasing the average density, viscosity, and volume of the moving fluid.
facing very energetic wind and wave systems will tend to hold only large rocks as smaller particles will be held in suspension in the turbid water column and carried to calmer areas by longshore currents and tides. Coastlines that are protected from waves and winds will tend to allow finer sediments such as clay and mud to precipitate creating and mangrove forests. The shape of a beach depends on whether the waves are constructive or destructive, and whether the material is sand or shingle. Waves are constructive if the period between their is long enough for the breaking water to recede and the sediment to settle before the succeeding wave arrives and breaks.
Fine sediment transported from lower down the beach profile will compact if the receding water percolates or soaks into the beach. Compacted sediment is more resistant to movement by turbulent water from succeeding waves. Conversely, waves are destructive if the period between the wave crests is short. Sediment that remains in suspension when the following wave crest arrives will not be able to settle and compact and will be more susceptible to erosion by Longshore drift and receding tides. The nature of sediments found on a beach tends to indicate the energy of the waves and wind in the locality.
Constructive waves move material up the beach while destructive waves move the material down the beach. During seasons when destructive waves are prevalent, the shallows will carry an increased load of sediment and organic matter in suspension. On sandy beaches, the turbulent backwash of destructive waves removes material forming a gently sloping beach. On pebble and shingle beaches the swash is dissipated more quickly because the large particle size allows greater percolation, thereby reducing the power of the backwash, and the beach remains steep. Compacted fine sediments will form a smooth beach surface that resists wind and water erosion.
During hot calm seasons, a crust may form on the surface of ocean beaches as the heat of the sun evaporates the water leaving the salt which crystallises around the sand particles. This crust forms an additional protective layer that resists wind erosion unless disturbed by animals or dissolved by the advancing tide. Beach cusps and horns form where incoming waves divide, depositing sand as horns and scouring out sand to form cusps. This forms the uneven face on some sand . White sand beaches look white because the quartz or eroded limestone in the sand reflects or Scattering sunlight without significantly absorbing any colors.
Over long periods of time, well-stabilized foreshore areas will tend to accrete, while unstabilized foreshores will tend to erode, leading to substantial changes in the shape of the coastline. These changes usually occur over periods of many years. Freak wave events such as tsunami, tidal waves, and storm surges may substantially alter the shape, profile and location of a beach within hours.
Destruction of flora on the berm by the use of herbicides, excessive pedestrian or vehicle traffic, or disruption to freshwater flows may lead to erosion of the berm and dunes. While the destruction of flora may be a gradual process that is imperceptible to regular beach users, it often becomes immediately apparent after storms associated with high winds and freak wave events that can rapidly move large volumes of exposed and unstable sand, depositing them further inland, or carrying them out into the permanent water forming offshore bars, lagoons or increasing the area of the beach exposed at low tide. Large and rapid movements of exposed sand can bury and smother flora in adjacent areas, aggravating the loss of habitat for fauna, and enlarging the area of instability. If there is an adequate supply of sand, and weather conditions do not allow vegetation to recover and stabilize the sediment, wind-blown sand can continue to advance, engulfing and permanently altering downwind landscapes.
Sediment moved by waves or receding floodwaters can be deposited in coastal shallows, engulfing reed beds and changing the character of underwater flora and fauna in the coastal shallows.
Burning or clearance of vegetation on the land adjacent to the beach head, for farming and residential development, changes the surface wind patterns, and exposes the surface of the beach to wind erosion.
Farming and residential development are also commonly associated with changes in local surface water flows. If these flows are concentrated in stormwater drains emptying onto the beach head, they may erode the beach creating a lagoon or delta.
Dense vegetation tends to absorb rainfall reducing the speed of runoff and releasing it over longer periods of time. Destruction by burning or clearance of the natural vegetation tends to increase the speed and erosive power of runoff from rainfall. This runoff will tend to carry more silt and organic matter from the land onto the beach and into the sea. If the flow is constant, runoff from cleared land arriving at the beach head will tend to deposit this material into the sand changing its color, odor and fauna.
The retention of the freshwater may also help to maintain underground water reserves and will resist salt water incursion. If the surface flow of the runoff is diverted and concentrated by drains that create constant flows over the beach above the sea or river level, the beach will be eroded and ultimately form an inlet unless longshore flows deposit sediments to repair the breach.
Once eroded, an inlet may allow tidal inflows of salt water to pollute areas inland from the beach and may also affect the quality of underground water supplies and the height of the water table.
In extreme cases, beach nourishment may involve placement of large pebbles or rocks in an effort to permanently restore a shoreline subject to constant erosion and loss of foreshore. This is often required where the flow of new sediment caused by the longshore current has been disrupted by construction of harbors, breakwaters, causeways or boat ramps, creating new current flows that scour the sand from behind these structures and deprive the beach of restorative sediments. If the causes of the erosion are not addressed, beach nourishment can become a necessary and permanent feature of beach maintenance.
During beach nourishment activities, care must be taken to place new sediments so that the new sediments compact and stabilize before aggressive wave or wind action can erode them. Material that is concentrated too far down the beach may form a temporary groyne that will encourage scouring behind it. Sediments that are too fine or too light may be eroded before they have compacted or been integrated into the established vegetation. Foreign unwashed sediments may introduce flora or fauna that are not usually found in that locality.
Brighton Beach, on the south coast of England, is a shingle beach that has been nourished with very large pebbles in an effort to withstand the erosion of the upper area of the beach. These large pebbles made the beach unwelcoming for pedestrians for a period of time until natural processes integrated the naturally occurring shingle into the pebble base.
The development of the beach as a popular leisure resort from the mid-19th century was the first manifestation of what is now the global tourist industry. The first seaside resorts were opened in the 18th century for the aristocracy, who began to frequent the seaside as well as the then fashionable spa towns, for recreation and health. (2025). 9780273701613, Pearson Education. ISBN 9780273701613 One of the earliest such seaside resorts, was Scarborough in Yorkshire during the 1720s; it had been a fashionable spa town since a stream of acidic water was discovered running from one of the cliffs to the south of the town in the 17th century. The first rolling were introduced by 1735.
The opening of the resort in Brighton and its reception of patronage from King George IV, extended the seaside as a resort for health and pleasure to the much larger London market, and the beach became a centre for upper-class pleasure and frivolity. This trend was praised and artistically elevated by the new Romanticism ideal of the picturesque landscape; Jane Austen's unfinished novel Sanditon is an example of that. Later, Queen Victoria's long-standing patronage of the Isle of Wight and Ramsgate in Kent ensured that a seaside residence was considered as a highly fashionable possession for those wealthy enough to afford more than one home.
The growth was intensified by the practice among the Lancashire cotton mill owners of closing the factories for a week every year to service and repair machinery. These became known as . Each town's mills would close for a different week, allowing Blackpool to manage a steady and reliable stream of visitors over a prolonged period in the summer. A prominent feature of the resort was the promenade and the , where an eclectic variety of performances vied for the people's attention. In 1863, the North Pier in Blackpool was completed, rapidly becoming a centre of attraction for upper class visitors. Central Pier was completed in 1868, with a theatre and a large open-air dance floor..
Many of the popular beach resorts were equipped with , because even the all-covering swimsuit of the period was considered immodest. By the end of the century the English coastline had over 100 large resort towns, some with populations exceeding 50,000.
Continental European attitudes towards gambling and nakedness tended to be more lax than in Britain, so British and French entrepreneurs were quick to exploit the possibilities. In 1863, Charles III, Prince of Monaco, and François Blanc, a French businessman, arranged for and carriages to take visitors from Nice to Monaco, where large luxury hotels, gardens and casinos were built. This area of Monaco was then renamed Monte Carlo after prince Charles III.
Commercial sea bathing spread to the United States and parts of the British Empire by the end of the 19th century. The first public beach in the United States was Revere Beach, which opened in 1896. During that same time, Henry Flagler developed the Florida East Coast Railway, which linked the coastal sea resorts developing at St. Augustine, FL and Miami Beach, FL, to winter travelers from the northern United States and Canada on the East Coast Railway. By the early 20th century surfing was developed in Hawaii and Australia; it spread to southern California by the early 1960s. By the 1970s cheap and affordable air travel led to the growth of a truly global tourism market which benefited areas such as the Mediterranean, Australia, South Africa, and the coastal Sun Belt regions of the United States.
In more than thirty countries in Europe, South Africa, New Zealand, Canada, Costa Rica, South America and the Caribbean, the best recreational beaches are awarded Blue Flag status, based on such criteria as water quality and safety provision. Subsequent loss of this status can have a severe effect on tourism revenues.
Beaches are often dumping grounds for waste and litter, necessitating the use of and other cleanup projects. More significantly, many beaches are a discharge zone for untreated sewage in most underdeveloped countries; even in developed countries beach closure is an occasional circumstance due to sanitary sewer overflow. In these cases of marine discharge, waterborne disease from feces and contamination of certain marine species are a frequent outcome.
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. In a zero-depth entry pool, the bottom surface slopes gradually from above water down to depth. Another approach involves so-called , 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. Such beaches are often not recognized by consumers as artificial. A famous example of beach nourishment came with the replenishment of Waikiki in Honolulu, Hawaii, where sand from Manhattan Beach, California was transported via ship and barge throughout most of the 20th century in order to combat Waikiki's erosion problems. The Surfrider Foundation has debated the merits of with members torn between their desire to support natural coastal environments and opportunities to enhance the quality of surfing waves. Similar debates surround beach nourishment and snow cannon in sensitive environments.
In some places, such as Florida, it is not always clear which parts of a beach are public or private.
Public access to beaches is protected by law in the U.S. state of Oregon, thanks to a 1967 state law, the Oregon Beach Bill, which guaranteed public access from the Columbia River to the California state line, "so that the public may have the free and uninterrupted use". Public access to beaches in Hawaii (other than those owned by the U.S. federal government) is also protected by state law.
A well-designed beach access should:
Ocean beaches are habitats with organisms adapted to salt spray, tidal overwash, and shifting sands. Some of these organisms are found only on beaches. Examples of these beach organisms in the southeast US include plants like sea oats, sea rocket, beach elder, beach morning glory ( Ipomoea pes-caprae), and beach peanut ( Okenia hypogaea), and animals such as mole crabs ( Hippoidea), coquina clams ( Donax), , and white beach tiger beetles.
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