NUMERICAL SIMULATION OF TSUNAMI HAZARDS IN SOUTH ATLANTIC COAST: CASE OF THE CITY OF AGADIR – MOROCCO: PRELIMINARY RESULT

Abstract

The coastal zone is a highly complex area because of its location at the interface between land and sea and as a preferred location for many forms of development. A mega tsunami from the Canary Islands will hit not only the Atlantic coasts of Morocco, but also Spain, Portugal, Great Britain and even reach US shores.

A slight earthquake or possible volcanic eruption can trigger one of the most violent natural disasters in history. Indeed, according to Steven Ward and Simon Day (2001) the west flank of the Cumbre Vieja volcano, located on the island of Palma is unstable and could, as a result of a future eruption, collapse into the ocean. It would be in the worst scenario of a huge piece of 25 km long, 15 wide and 1,400 meters thick that would come off, a total of 500 cubic kilometers of land and rocks. This wave could reach 50 meters of height, once arrived on the Moroccan coasts. In this study, a numerical inundation and vulnerability models are used to identify the location and nature of current and future hazards and risk on the Moroccan coast to better understand the tsunami hazard and vulnerability along the Moroccan coast. We have worked on the correction of coastlines from satellite imagery on Google Earth and the digitization of bathymetric and topographic maps, in order to create digital elevation models (DEM). We have also studied the vulnerability assessment of the buildings by using the BTV model (Building Tsunami Vulnerability) such as a combination of tsunami inundation numerical modelling, field survey data and geographic information system.