A beach is a gently sloping, sandy strip of land that lies in or near the ocean. This narrow, gently sloping land is often used as a recreational destination. The term can also be applied to the area where a large river meets the sea. Beaches are found in almost one-third of the global coastlines. Some beaches are naturally shaped and others are artificial.
Most beaches are shaped by waves and winds. When a wave strikes a cliff, it may cause loose rocks and sediments to be carried inland. Sediments on the beach can vary from tiny particles to sand grains. These can be moved by wind, water, and saltation. If the tides are unusually high, a storm can create coastal flooding. Sand is also moved by ocean currents.
Some beaches have showers, lifeguard posts, shacks, hotels, and other amenities. Others are rocky. There are also beaches that are barren and desert-like. In many places, beaches are also associated with lakes and rivers.
Beaches are often influenced by weather systems, such as the El Nino-Southern Oscillation (ENSO). During the ENSO, sea level rise is a factor. However, the most important threat to beaches is natural coastal erosion. Many communities want to stop shoreline erosion and protect their beaches.
Sea walls can be constructed to prevent the erosive effects of the ocean. These structures can be made of rock or plastic. Floating plastic can prevent algae and other sea plants from growing. While this is an effective method of protecting sea plants, it can also hinder animals in the tide pool.
Beaches are an important part of the cultural landscape. Some communities invest in a series of seawalls to protect their beaches. They may be built of concrete or rock. Ideally, the material should be able to withstand the storms that occur at the beach.
Some beaches are actively restored by practices such as beach nourishment. For instance, the Sea Gate community in Coney Island, New York, invested in a series of seawalls to reduce the risk of erosion.
Another way of combating erosion is by using sand to replenish beaches. This strategy has been widely adopted in developed countries. Unfortunately, sand replenishment is not an effective long-term solution to the problem of coastal erosion.
Some of the world’s most popular and attractive beaches are artificial. In the United States, for example, Punaluu Beach in Hawaii is made of basalt. Although it is a green beach, it is made up of thousands of tiny fragments of olivine, a mineral. Similarly, the beaches of Tuvalu were eroded rapidly during the 1990s.
Although sand and gravel beaches are important recreational resources, they can also be a source of pollution. For example, small bits of plastic can be choking for birds. Other pollutants include sewage and toxic chemicals. To avoid such risks, visitors should not throw anything in the water or leave trash on the beach.
Despite the challenges, beach nourishment is a cost-effective, albeit slow, approach to fighting erosion. In some areas, it is the preferred strategy to combat erosion. It can also improve the habitat for selected species of biota.