Kite Beach in Dubai is a very popular destination for tourists and every year millions of people flaunt the beach for various reasons. This however has started to become an issue as the beach is starting to erode. Erosion is the wearing away of the land by the sea. This often involves destructive waves wearing away the coast. There are four main processes which cause coastal erosion. These are corrasion/abrasion, hydraulic action, attrition and corrosion/solution. Corrosion is the slight acidity of sea water causing bits of the cliff to dissolve. Corrasion is when rocks are thrown in the cliffs by waves and they break off parts of the cliff. Hydraulic action is when sea water and air get trapped in cracks. The increasing pressure of the water and air cause the rocks to crack. Attrition is when rocks, sands and stones are thrown into each other by the sea current and waves. Large scale coastal developments such as the Palm Jumeirah and the World Islands have increased the rate at which Dubai's beaches are eroding. To maintain the existing coastline, hundreds of tonnes of sand would need to be dumped on affected stretches on a regular basis. The rotation of beach sand is caused by the angle at which the Arabian Gulf current hits the coast. There are many ways to help reduce the problem of coastal erosion. One of them being, beach nourishment. It is a soft engineering approach to coastal protection which involves the artificial addition of sediment of suitable quality to a beach area that has a sediment deficit. Nourishment can also be referred to as beach recharge, beach fill, replenishment, re-nourishment and beach feeding. It is important to note that beach nourishment does not halt erosion, but simply provides sediment from an external source, upon which erosional forces will continue to act. In this sense, beach nourishment provides a sacrificial, rather than a fixed barrier against coastal erosion. Another method is the installation of groynes. These are wooden barriers built at right angles to the beach. They prevent the movement of beach material along the coast by longshore drift and allow the build up of a beach. Beaches are a natural defense against erosion and an attraction for tourists. The only issue is that they are costly to build and maintain. Another alternate method that can be used to prevent coastal erosion would be the installation of seas walls. This is a wall built on the edge of the coastline. It protects the base of cliffs, land and buildings against erosion. It can also prevent coastal flooding in some areas. Even though this might be useful it can have some major cons to it. Curved sea walls reflect the energy of the waves back to the sea. This means that the waves remain powerful. Over time the wall may begin to erode. The cost of maintenance is also high. These are some ways by which the coastline of UAE can be protected thought environmental engineering.
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