A new approach to assess long-term lava flow hazard and risk using GIS and low-cost remote sensing: the case of Mount Cameroon, West Africa
Abstract:Mount Cameroon (MC), West Africa's most active volcano, is a typical example of a hazardous volcano in a densely populated area, often inflicting damage by lava flows. The spatial variation of the lava flow hazard has not been mapped systematically at MC and at many other volcanoes in developing countries because they are insufficiently documented and not continuously, systematically monitored with integrated state-of-the-art methods. Sophisticated lava flow models requiring the specification of numerous physical properties cannot yet be applied in such cases. Hence, a low-cost approach is proposed to assess the medium- to long-term spatial variation of lava flow hazard. The 'lava flow zonation system using low-cost methods' (LAZSLO) approach takes advantage of freely available topographic data and moderate-resolution (10-100 m) satellite imagery. For any eruption, the formulation used here expresses the probability of lava flow invasion at any location as a product of the spatial variation of eruption probability and exposure of low-lying terrain to lava flow reach. The last term is derived by determining the upslope area from where lava flows can invade a given site. A standard UNESCO formula is then used to estimate the lava flow risk. Hazard assessment results at MC indicate that the southwest and northeast flanks are the most hazardous from lava flows, whereas the risk of damage is greatest in the area between Limbe, Mapanja and Batoke, where industrial, urban and tourism infrastructures are developing rapidly. The presented approach can be applied to assist local authorities with disaster preparedness and emergency planning at many poorly studied volcanoes, particularly in developing countries with limited financial resources.
Document Type: Research Article
Affiliations: 1: Mercator and Ortelius Research Centre for Eruption Dynamics, Department of Geology and Soil Science, Ghent University, 9000 Ghent, Belgium,Laboratory of Soil Science, Department of Geology and Soil Science, Ghent University, 9000 Ghent, Belgium 2: Mercator and Ortelius Research Centre for Eruption Dynamics, Department of Geology and Soil Science, Ghent University, 9000 Ghent, Belgium 3: C.I.R.A.M., Department of Earth Sciences, University 'Federico II' of Naples, 80138 Napoli, Italy 4: Department of Geology and Environmental Sciences, University of Buea, Buea, South West Province, Cameroon 5: Laboratory of Soil Science, Department of Geology and Soil Science, Ghent University, 9000 Ghent, Belgium
Publication date: November 1, 2008