RECENT VARIATIONS IN SPACE-TIME OF RAINFALL SETTINGS AND THEIR IMPACT ON FLOW RIVER MARAHOUÉ (IVORY COAST).

Abstract

The aim of this study is to analyze the evolution of rainfall especially after 2000 and its impact on runoff in the watershed Marahoué. In this perspective, statistical approaches have been implemented over a series of rainfall and flow data on the period from 1970 to 2008. Over the period 1970-2000, statistical analyzes show an alternation of wet period (1970-1980) and dry (1981-2000). The dry period is shown by a rainfall deficit of 15% to 37%. It was also observed a return to wet period of 2001-2008 in the basin. The rainfall deficit period that recorded the basin has had a significant impact on flows with declines of around 50% in the hydrometric stations. However, since 2001, there has been higher than normal flows in the basin after the rainfall recovery. This highlights the significant influence of rainfall variation on the flow rates of Marahoué River.