A beach is a landform alongside a body of water, consisting of loose material that may be composed of rocks (such as gravel, cobbles and shingle), organic materials such as algae and seaweeds, or purely inorganic substances such as silt, clay or sand. Beaches are formed by waves agitating the surface of the water, and can be shaped, contoured, and eroded in various ways. Beaches occur both on the ocean coastline and along lakes and rivers.
A natural beach is created by the actions of wave, wind and tidal currents, but human influences can also alter beaches rapidly. This can be a result of direct human impacts such as construction activities and poor design on sand dunes, or indirect environmental impacts such as the use of chemical products which cause pollution to enter bodies of water or sediment. In addition, natural and human occurrences can change the size, shape and location of a beach within hours.
Coastal erosion is the most important factor determining the character of a beach, but other factors can play a role as well, depending on the geological conditions and climate. For example, the presence of a reef or an active stream will impact the size of a beach, as will whether the area is sheltered by barrier islands or baymouth barriers.
There are different types of beaches that are ideal for surfing, and the type of beach a surfer chooses to visit can greatly influence their experience. Among the most popular beach breaks are point break, A-frame, and reef break. Each of these beach breaks presents unique features that surfers can take advantage of to create impressive rides, and having a strong understanding of the different beach break characteristics is crucial to finding the right spot for surfing.
The crest of a wave is its highest part, and it’s usually the most dramatic and visible aspect of the entire break. The crest is the first part of the wave to be shaped, and can have an effect on the speed and direction of a wave. The sand on a beach can also have an impact on the crest’s shape, as can the sea floor.
A sand bar is a flat patch of sand that is separate from the main shoreline. A sandbar can be surrounded by shallow, clear waters, or by deep, murky waters. The sand on a sandbar is often finer and more sandy than the surrounding beach, and it can have an effect on how a wave forms. It’s common for sandbars to develop at areas where the seafloor has a gentle slope, but sand bars can also form at more rugged areas. This is especially true in areas where groyne fields are used to stabilize beaches.