L'approche géohistorique pour la cartographie des risques naturels : application au risque de submersion marine à Ouvéa (Nouvelle-Calédonie)

Abstract

Through a geohistorical approach, a database on cyclonic risk was created in New Caledonia, based on 220 events identified since the 19th century (K. GODET, 2016 ; P. DUMAS et al., 2019). In this article, we focus on one particular event in this database: the February 1951 hurricane in Ouvea. This choice is explained that over our study period it was the largest marine flooding due to a cyclone that we were able to document for this island. Our objective is to discuss the value of the geohistorical approach for the production of prevention tools adapted to the local context and aimed at both populations and institutions. We will focus our article on the construction of a specific prevention instrument: the map reconstruction marine flooding during this cyclone. The elaboration of this map was based on the compilation of written documentation from several sources (ecclesiastical and written press), and oral documentation (testimonies and life stories). These diverse sources made it possible to isolate quantitative and qualitative information at different spatial scales. This reconstruction exercise will allow us to question the nature of the documents useful for its realization. This will make it possible to open up reflection on the dimensions related to the production of a mapping tool by integrating a more general consideration of the culture of risk and on the modes of representation and associated knowledge of populations.

Keywords

• risk
• mapping
• geohistory
• prevention
• cyclone
• submergence