Erosion is the "carrying away or displacement of solids (sediment, soil, rock and other particles) usually by the agents of currents such as, wind, water, or ice by downward or down-slope movement in response to gravity or by living organisms." Beach (or coastal) erosion is "the wearing away of land or the removal of beach or dune sediments by wave action, tidal currents, wave currents, or drainage." While beaches may be formed in part by erosion, human influence is weighing heavily on our coastlines today?for example, barrier islands.
According to HowStuffWorks.com, "Because barrier islands are popular vacation spots, many are being developed. Resort communities are being built on them including high-rise hotels, condominiums and golf courses. To accommodate these structures, sand dunes are destroyed and salt marshes and barrier flats are filled in." Another familiar culprit is global warming. The Woods Hole Oceanographic Institute explains, "The processes at work along the coast are incredibly complex...sometimes conflicting and counterintuitive. But almost all scientists agree that beach erosion is becoming more severe as sea level rises."
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