A beach is a gently sloping strip of land that is rich in material from the sea. These materials include sand, pebbles, rocks, and seashell fragments. The majority of these materials were formed over many years by the weathering processes of water and wind. The waves can erode large boulders down to tiny grains of sand.
There are many different types of beaches. Some are natural while others are artificially created. Artificial beaches are usually constructed along a coastline. An example of such a beach is Brighton Beach, in England. The beach originally consisted of large pebbles that made walking on it difficult. However, the natural process of erosion incorporated the shingle into the pebble base to create a more pedestrian-friendly beach.
The composition of a beach largely depends on its location and weather conditions. Some beaches are composed of coarse grain sand, while others are composed of finer grain. The finer the sand, the more water it absorbs. Sand-covered beaches tend to have gentle slopes and a shallow slope, which allows more water to flow down.
Sand and other materials that build up on a beach are called berms. They form when a beach is exposed to energetic wind systems. They move sand, which is influenced by the size of particles and their state of compaction. Sediment that is compacted will be more resistant to erosion, while sediment in suspension will not settle and may be more susceptible to longshore currents.
Generally, the most dynamic part of a beach is the surf zone. Breaking waves occur when the wave crest is at least 1.5 times the height of the wave. When waves break, they change their shape and move shoreward in broken white water. Sometimes these waves can be pushed back into the ocean by rip currents.
Each beach has a unique profile. This is what characterizes the overall landscape of the beach. Some are warm and lush, while others are rocky or barren. During colder months, beaches can be cold and rocky. Some beaches are even frozen over. At high latitudes, beach conditions can be so severe that sea ice can form on the shore.
Pollution on beaches is a huge problem. It affects about 800 species of marine life worldwide. Each year, 100,000 seabirds, sea turtles, seals, and other animals die due to plastic pollution. In addition, toxic materials can move up the food chain and even make their way into human stomachs. The sand on the beach can also be contaminated.
The formation of a beach requires a base, which is usually bedrock geology. In addition, wave action is a key factor in shaping beaches. Wave currents can move sediment onshore in a positive or negative way. Depending on the conditions of the local wave action, sand and rocks may settle in different densities and structures, resulting in distinct colors and gradients.