A GIS-Based Integrated Approach for the Assessment of Volcanic Risk

F. Leone¹, T. Lesales², J-C. Gaillard³

¹ Department of Geography, Université Paul Valery Montpellier III,
Route de Mende, 34199 Montpellier, France.
Email: Frederic.Leone@univ-montp3.fr
² Department of Geography, Université des Antilles et de la Guyane,
97275 Schoelcher, Martinique, France.
Email: Thierry@mount-pelee.com
³ Department of Geography, College of Social Sciences and Philosophy, University of the Philippines,
Diliman, Quezon City, Philippines 1101.
Email: jcgaillard@kssp.upd.edu.ph

Abstract

This study suggests an innovative GIS-based integrated approach for the assessment of volcanic risk. This is based on a 5-step methodology which has been developed at Mt. Pelée volcano, in Martinique, a French island of the Lesser Antilles. The first stage of the methodological framework integrates the spatial extent of volcanic hazards for different eruptive scenarios. The second stage covers an assessment of the elements (especially the buildings) that may be affected in the event of an eruption and defines their probability of being damaged by given volcanic hazards. A computerized analysis using GIS eventually leads to an absolute loss risk index for a 500-meter grid. The fourth stage consists in designing regulative land use maps which should orient and limit the occupation of areas exposed to severe hazards. Finally, the present methodology includes the collective representation or the perception of a future eruption by surrounding communities based on survey data. The GIS technology further enables to produce maps at all steps of the suggested framework and thus underscores spatial variations in risk level. These maps turn out to be powerful communication tools which help planners and disaster authorities in mitigating damages from volcanic hazards. Hopefully, this integrated approach for the evaluation of volcanic risk may be tested in the Philippines in the near future.