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A coastal development hazard is something that affects the natural environment by man-made products. As coasts become more developed, the vulnerability component of the equation increases as there is more value at risk to the hazard. The likelihood component of the equation also increases in terms of there being more value on the coast so a higher chance of hazardous situation occurring.〔 Fundamentally humans create hazards with their presence. In a coastal example, erosion is a process that happens naturally on the Canterbury Bight as a part of the coastal geomorphology of the area and strong long shore currents.〔〔 This process becomes a hazard when humans interact with that coastal environment by developing it and creating value in that area. In Burton 1978 ''‘The Environment as Hazard’'' a natural hazard is defined as the release of energy or materials that threaten humans or what they value.〔 In a coastal context these hazards vary temporally and spatially from a rare, sudden, massive release of energy and materials such as a major storm event or tsunami, to the continual chronic release of energy and materials such long-term coastal erosion or sea-level rise.〔〔 It is this type coastal hazard, specifically around erosion and attributes surrounding erosion that this article will focus on. == Coastal population growth and development on coasts == Globally the number of people living on the coast is increasing. It has been stated that there has been over a 35% increase in the population of people living on the coasts since 1995.〔 The average density of people in coastal regions is 3 times higher than the global average density.〔 Historically city development especially large cities were based on coasts due to the economic benefits of the ports. In 1950 there were only 2 megacities (cities with greater than 8 million people) in the coastal zone, London and New York. By the mid-nineties there were 13.〔 Although coastal areas globally have shown population growth and increases in density, very few in-depth quantitative global studies of population have been carried out, especially in terms of distribution across specific environs, like coasts.〔〔 The spatial distribution and accuracy of global data must be significantly improved before realistic quantitative assessments of the global impacts of coastal hazards can be made. As currently much of the data is collected and analysed in the aftermath of disasters.〔 Historic studies have put estimates of the number of deaths due to cyclones over the last 200 years around the Bay of Bengal exceeding 1.3 million.〔 However, in developed countries, as can be expected, the death toll is significantly lower but the economic losses due to coastal hazards are increasing. The United States of America (USA) for example had major losses in Hurricane Andrew, which hit Florida and Louisiana in 1992.〔 This rushing to the coast is exhibited in property value. A study by Bourassa et al. (2004) found in Auckland, New Zealand, wide sea views contributed on average an additional 59% to the value of a waterfront property. This effect diminished rapidly the further from the property was from the coast. In another study it was found that moving 150m away from the Gulf of Mexico lowered property values by 36%.〔〔 Insurance premiums in coastal hazard areas are an inconsequential determinant of property values, given the significant amenity values provided by the coast in terms of views and local recreation. Sea-level rise, coastal erosion, and the exacerbating interaction between these two natural phenomena are likely to pose a significant threat for the loss of capital assets in coastal areas in the future.〔 It is hard to say if the vulnerability to coastal hazards by those residing there is perceived yet dominated by the amenity value of coasts or simply ignored. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Coastal development hazards」の詳細全文を読む スポンサード リンク
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