III. A NATURAL HAZARD-PRONE BUILT ENVIRONMENT: JAMAICA AND THE CAPITAL CITY, KINGSTON We use the example of Jamaica to present an analysis of hazards, vulnerability and approaches to disaster risk reduction. Kingston, the capital city Jamaica is the most urbanized and populous city in the West Indies. Its vulnerability to multiple natural hazards is due primarily to inherent physical factors arising largely from geological history (Ahmad, 1996, Ahmad, 1998; Ahmad and Lyew-Ayee Jr., 2005, Ahmad et al., 1993; Carby and Ahmad, 1995; Gupta and Ahmad, 1999a and 1999b). The island forms a part of the geologically active earthquake zone that defines the central section of the boundary between the Caribbean and the North American tectonic plates (Fig. 1.3). The picturesque landscapes on the island primarily owe their existence to a series of land movements during the Holocene period1 of Earth’s history. The nature of bedrock, tectonic history and hazardous processes shape landforms on Jamaica. It is an area of geologically young landforms, weathering-limited steep hill slopes, high annual precipitation and periodic short duration and high magnitude rainfall from various types of tropical storms which often reach hurricane force. Tropical storms and tropical depressions are annual events creating conditions for the simultaneous occurrence of landslides, sediment floods and water floods island-wide. Major towns are located on coastal alluvial fans. Factors that heighten Jamaica’s vulnerability to natural disasters include development in highrisk areas, lack of adherence to building codes, high levels of poverty, and environmental degradation. The island’s water supply and road network are disrupted by recurrent disasters. This is well known for much of Jamaica. The hazards which affect the island most frequently are landslides, sediment floods and water floods (Ahmad, 2005a). However, the costs of rehabilitation and reconstruction have been increasing in the wake of recent natural disasters especially the damage to infrastructure. Carby and Ahmad (1995) have examined the vulnerability of roads and water systems to landslides and flooding by comparing impacts of a large-scale event, the 1988 hurricane Gilbert, and the relatively small-scale events of recurrent rainfall from non-hurricane storms of May 21-22, 1991, and the storm, Gordon of November 10-13, 1994. Urban vulnerability to landslides and flooding is highlighted by these two events 1
Holocene period: less than 10,000 years before present
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