What Causes Beach Erosion?
Beach erosion is caused by a number of factors. The ubiquitous desire to live near the sea, tropical storms, the gradual sinking of coastal land (also known as sea-level), unsuccessful efforts to reduce erosion that had adverse effects, and global warming. Many people cannot resist the want to live in a beach house. Most people have beach houses for vacations or as a summer home. But they do not think of the effects that could have on their house nor do they consider the effect it will have on the beach. (Hanley, 1998)
A Deeper Look at the Effects of Population, Global Warming, and Tropical Storms on Beach Erosion
All of the causes go hand in hand. One cause leads to the next and so on and so forth. The more populated a region becomes, the more likely subsidence will occur. America’s population is growing by about 2.6 million people every year. Where humans interfere with river systems, sediment is taken out to sea or blocked upriver, creating more severe shoreline erosion and a relative increase in sea level. The heavy development of beach resorts and other coastal areas decreases the wetlands ability to slowly reestablish them upland. (Kossof, 1998 and, Matt Carroll 1996)
Lately, one of the major causes of beach erosion has been greenhouse warming. Greenhouse gases such as carbon dioxide, nitrous oxide, methane and chlorofluorocarbons are generated by human activity. These gases are accumulating in the atmosphere and trapping radiation from the sun. The massive destruction of trees leaves fewer forests to recapture the main greenhouse gas, which is carbon dioxide. The ambush of global warming is likely to increase the frequency of tropical storms, which tear sand away from beaches. The increasing concentrations of greenhouse gases in the atmosphere are likely to raise the average temperature. (Jacobson 1989)
The waves from a tropical storm carry away sand that the beach has been storing in dunes. The sand is placed at the bottom of the ocean floor. After a storm, a vertical cut allows people to see that the waves claimed large portions of the shore. Big waves have more power to hold more sand particles in suspension and remove from the beach than smaller waves. The energy and steepness of the large wave carry the sand further into the sea. Thus, taking away from the beach. (Jacobson 1990)
Beach Erosion in the United States
Nearly half of the United States population lives within eighty kilometers of the coast. The beach is the boundary between the water and the land. It is an area for human settlement and agriculture. The beaches of the United States and the rest of the world are swarming with economic and ecological growth. The United States has nineteen thousand miles of beaches. Five hundred of those miles have set aside in ten national seashores. These particular seashores are protected by their own legislation and managed by the National Park Service. A beach erodes because the supply of sand to the beach cannot keep up with the loss of sand to the sea. Most sand is transported from inland through rivers and streams. The damming of most waterways in the United States has prevented a major supply of sand from getting to the beaches. Sand can also be transported from beach to beach along shoreline but this is mostly just a redistribution of sand that is already on the coast. The problem of beach loss can be inflated if sea level rises relative to the land. If this occurs new beaches can be created further inland. “But when the encroaching sea comes against people’s property the tendency is for people to try and stop it. These individuals armor the shoreline with seawalls, revetments, jetties, etc. These have negative effects on beaches because once seawater reaches them it bounces off them with more energy than a wave washing back off a normal sand beach. With this more sand is carried off shore, promoting beach loss. Piers, otherwise known as jetties, placed perpendicular to the beach disrupt along-beach current causing sand loss downstream of the jetty.” (Graham 1994)
Effects of Beach Erosion
Beach erosion is problem that all people need to take more seriously because the long-term effects are far more extreme than most people can imagine. The effects of beach erosion can be as negligible as a deep hole in the sand or a large pit in the sand. However the effects can also be very destructive. Beach erosion can cause a house to fall into the ocean. The effects are also devastating on the ecosystem of the beach. The different life living in the sand and in the reefs are killed. ( Jacobson,1989)
