Etude de la sécheresse, cas du bassin versant de la Soummam.

Abstract

Droughts are part of extreme weather events; they create serious social, economic and environmental consequences. This work deals with an evolution of the drought study periods between 1980 and 2011, as well as the regionalization of drought in the watershed of Soummam. The standardized precipitation index and the principal component analysis are used to understand the importance and the temporal and spatial evolution of the drought on the whole watershed, these methods have proven as useful indicators of the phenomenon. The SPI has led us to conclude that 2001 was the year the most affected by drought, while 2002 was the year the least affected by drought. To understand the extent of the phenomenon, the PCA allowed observing that the drought intensifies from north to south, in the direction of the decrease in rainfall. Thus we can conclude that the most vulnerable areas are those that are the least watered from the watershed. This will allow us to have an overall idea about past and future climate scenarios of Soummam.