Erosion

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Coastal Erosion
The beaches of North Carolina's coastline face an ongoing threat: coastal erosion. Though mostly gradual and relatively unnoticeable over the course of a year or two, the rising sea level combined with a season of storms or hurricanes can cause anywhere from a few feet to hundreds of feet of this delicate shoreline being stripped away. Solutions are constantly being studied and discussed, but often, the solution to erosion can be just as damaging as erosion itself. While vacationers are all but guaranteed to enjoy decades of happy beach days in the future, the issue of coastal erosion and its potentially devastating effects on our shorelines remains on the minds of locals and visitors. Coastal erosion is the wear2ing away of land or the removal of beach or dune sediments by wave action, tidal currents, wave currents or drainage. Waves generated by storms, wind or even fast-moving motorcraft traveling close to shore cause coastal erosion. Erosion may take the form of long-term losses of sediment and rocks or merely the temporary redistribution of coastal sediments. In other words, erosion in one location may result in a larger beach nearby, as the sand is veritably "moved" from one stretch of beach to another. On rocky coasts, coastal erosion results in dramatic rock formations in areas where the coastline contains rock layers or fracture zones with different resistances to erosion. Softer rocky areas become eroded much faster than harder ones, and erosion on rocky coasts can literally take centuries of battering waves to make a noticeable impression. On sedimentary coasts, however, like the beaches of North Carolina, coastal erosion typically poses more of a danger to human settlements like coastal towns and oceanfront structures than it does to nature itself, and human interference can also increase coastal erosion. For example, a town called Hallsands in Devon, England was a coastal village that was washed away overnight, an event thought to be caused by the dredging of shingle (beach gravel) from the bay in front of the village. Erosion is not necessarily a bad thing. In fact, throughout the course of history, erosion has directly led to the opening of new inlets and harbors and has created new feeding grounds for countless coastal species. In the long term and at a gradual pace determined by nature, erosion has gently changed maritime ecosystems in a positive way. However, human interference, combined with global warming, can speed up the process of erosion with effects that may not have been intended by Mother Nature, and this is when erosion can be a concern. Causes of Coastal Erosion

As a general rule, North Carolina's beaches erode more in the stormy fall and winter months than in the calm summer months. It is not unusual for the mean high water line to move landward temporarily by 75 to 100 feet during the stormy season. Of course, when an ocean shoreline is hit directly by a hurricane, beachfront erosion can be even more dramatic. Inlets are also affected by seasonal storms and can change configuration rapidly and severely as tremendous amounts of water and sand flow through them. In severe storms, it is even possible for new inlets to form and existing inlets to close. Erosion associated with storms is often severe because large quantities of sand can be moved quickly offshore from the beach and dunes. This type of erosion is usually called "short-term" because the shoreline can return to its original profile as the stormy conditions return calm. Erosion can be caused by a number of factors, some short-term and some long-term, like the changes in coastline shape that are caused by the ever-present currents that barrage our shore. A current is defined as a large mass of continuously moving ocean water, and surface ocean currents are mainly wind-driven and occur in all of the world's oceans. One of the largest and fastest moving surface currents in the world, The Gulf Stream, runs parallel to...
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