Tendances et ruptures au niveau des pluies journalières extrêmes en Côte d'Ivoire (Afrique de l'Ouest)

Abstract

Climate change is a reality which affects many climatic variables, including precipitation. Nevertheless, impacts on extreme events and in particular on daily extreme rainfall are not certain because few works have been devoted to them in West Africa. In this context, it was proposed to detect possible trends or step changes in the statistical properties (mean, variance) of daily extreme rainfall records using local and regional statistical tests. To detect these changes, the indices characterizing the maximum annual daily rainfall (PJmaxan), the annual number of daily rainfall greater than 50 mm (NJsup50) and the contribution of daily rainfall greater than 50 mm in annual rainfall (R(PJsup50/Pan)) were defined. The analysis of 44 rainfall stations in Ivory Coast for the period 1942-2002 does not show a change generalized for either mean or variance. However, by dividing the Ivory Coastinto climatically homogeneous regions, downward trends were observed in regions I (North) and IV (South East). © 2012 Copyright 2012 IAHS Press.