Article

Development of a morphodynamic indicator for sub-regional integrated coastal area management

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Abstract

The rapid development of infrastructure to cope with the expansion of the tourist industry along the coasts of the Mediterranean Sea has introduced numerous instabilities on the natural environment that are reflected by a long history of coastal planning and management efforts. The development of indicators has been established as a powerful approximation to characterizing certain measures of coastal state. Using the power and relative accuracy that wave propagation models have proved on non quantitative applications, a method is used in this paper that incorporates high resolution bathymetries and synthetic wave fields to produce characteristic energy settings in the nearshore region. The directional component of the wave forces are analyzed and a "cell" system depicted following basic gradients that should drive wave induced currents (and associated sediment transport) from a high momentum transfer area to a low momentum transfer area, corresponding to potential erosion and deposition events. Following this simple conceptual model, residual cells can be drawn and thus a cartographic version of potential erosion-deposition sites developed. This analysis provides repeatable and measurable ranked geographic data yielding an indicator of great potential use for decision makers and agencies monitoring coastal evolution. The analysis is performed along the eastern portion of the Costa del Sol in Andalusia, southern Spain, which environment is dominated by narrow beaches and occasional river deltas that influence sediment input as well as wave refraction and nearshore processes. The final maps, with the residual cells marked indicating points of potential erosion and deposition, has been presented and utilized as an aid to improve integrated coastal management by the Andalusian regional government allowing inventory and characterization for future reference.

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