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Map of the Caribbean region Coastal zone management, monitoring and defence mechanisms are now being designed and implemented in the Caribbean to mitigate and adapt to these threats. Flood prevention
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Coastal areas in the Caribbean have a high population density which is anticipated to increase in the future. For many of the islands, the coastal zone represents a high economic activity, as tourism based economies are predominant in the Caribbean. Historically and in recent times, coastal hazards such as hurricanes, tropical storms, tsunamis and...
Contexts in source publication
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... are typically realised through observations from space based systems such as GPS. (FIG, 2006) 2.3 Equipotential Surfaces Equipotential surfaces are surfaces of constant gravity potential. The gravitational potential of the earth depends on the distribution of mass density throughout the earth. ...
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... percent of the Caribbean population lives less than 100 kilometres from a coast. (Hinrichsen, Don, 2004) For the Caribbean (see Figure 2), the ocean and coastal environment is of strategic importance and constitutes a valuable development resource. All capital cities in the insular Caribbean are on the coasts. ...
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... surveys, however, result in spatial data that cannot be compared far less seamlessly integrated once they are not referenced to the same vertical datum, and therein lays the challenge, as a consistent vertical datum does not exist across the land-sea interface. (Parker, Milbert, et al 2002) The CARIB97 geoidal model is the main tool for determining orthometric heights in the Caribbean. There has been, in recent times, movement towards the use of the EGM 2008, which is a global model. ...
Citations
... The vertical position has two main factors according to the used reference surface; Ellipsoidal datum (is based on a geometric model) and the Equipotential surface (the geoid) (is the surface of constant gravity potential) [1]. Therefore, the vertical component has two different heights values Ellipsoidal heights/Geodetic heights (hi) and Orthometric heights (Hi). ...
... Equation (1) presents the mathematical relationship between (hi) and (Hi) as shown in Fig. (1), where (Ni) called the Geoid Undulation/Geoidal Height. Therefore, (Ni) value for any point (i) can be used to convert (Hi) value and (hi) value in both directions. ...
... ….... (1) Global Geopotential Models (GGMs) is being represented by the spherical harmonic coefficient which defines the potential of gravitational in the spectral domain [3]. Several GGMs are used to calculate (Ni) value at any point (i). ...
— Geoid Undulation value can be calculated by several GGMs and due to the huge area of Egypt, each GGM calculates a different undulation value of the same point, therefore the accuracy for the calculated geoid undulation values will affecting directly on the accuracy of the converting process between Geodetic height and Orthometric height. The main objective of this paper is investigating the accuracy of different Global Geo-Potential Models data which recently used over Egypt. Eight GGMs were selected to be tested in this study under different standards. 346 stations were regularly distributed over Egypt territories as network; these are bounded by latitudes [22° N, 31° N] and by longitudes [26° E, 36° E]. The methodology of this paper had been based on utilizing the least-squares theory, the Coefficient of Variation (C.V) ratio were calculated to compare the results for each selected GGM. Generally, the maximum (C.V) ratio reach 18.418 % of EIGEN-CG01C and the minimum ratio reach 16.829 % of EIGEN-GL04C. Finally, this paper recommends using six GGMs over Egypt territories, this is based on insignificant variations between these six GGMs after using, testing and analyzing the all geoid undulation values for the 346 stations.
