Beaches are areas of land that are located along the shoreline of the ocean. They are made up of various types of materials, including sand, gravel, cobbles, rock fragments, shells, and dirt. The material is carried to the beach by the wind or water. However, the exact materials that form a beach vary from place to place, depending on the climate, geology, and geologic history of the area.
Most beaches are comprised of sand. Sand particles are derived from erosion of rocks and headland. Sandy beaches often feature a man-made infrastructure, such as lifeguard posts and showers. Some sandy beaches have shacks, hotels, and changing rooms.
Other beach materials include sand, shell fragments, and clay patches. In some instances, seaweed and other seaweed-derived particles may also be present. Beaches may also contain other materials, such as rocks, pebbles, or other minerals. A beach can be hundreds of kilometers long, and the materials in its composition can change regularly.
During periods of erosion, beach material can be carried away from the beach by waves, wind, and ocean currents. Occasionally, beaches can be destroyed by sudden erosion or high winds. For example, a tsunami can disrupt the flow of sediment and cause beaches to erode. Large cyclonic storms can also damage beaches, resulting in a wave surge or debris-laden waters. Ocean currents can carry sediment hundreds of kilometers from the beach.
Beaches are important as a transitional biome between land and ocean. They provide protection for residents and are an important recreational activity for millions of people. However, beaches are susceptible to pollution, which can affect marine animals and plants, as well as human health. It is important to remember that beach visitors should avoid throwing waste in the ocean. Moreover, plastics and other floating waste can prevent sea plants and algae from developing.
Beaches are also an important refuge for marine mammals. These animals can become tangled in floating plastics and may not be able to find nutrients in the tide pools. Toxic waters can take days to wash out to the ocean, which can pose a danger to humans. If you visit a beach, never throw plastics, metals, or other waste into the ocean. Even small pieces of plastic may be hazardous to humans and birds.
There are three major groups of beaches. Barrier-island beaches, intermediate beaches, and dissipative beaches. Barrier-island beaches are narrow sand islands that are separated from the mainland by a bay or lagoon. Intermediate beaches are usually open coasts with a surf zone that is at least 300 to 500 meters wide.
Dissipative beaches are coastal environments that require large, ebbing, crashing, or pulsating waves. This type of beach is especially vulnerable to high-impact events, such as tsunamis. On the other hand, intermediate beaches need moderate waves to create a surf zone.
Because beaches are always moving, they can change dramatically from day to day. Changes can occur due to changes in the weather, the ebb and flow of the tides, and land-level fluctuations.