CARACTERISATION DES SEQUENCES DE SECHERESSE METEOROLOGIQUE A DIVERSES ECHELLES DE TEMPS EN CLIMAT DE TYPE SOUDANAIS : CAS DE L’EXTREME NORD-OUEST DE LA COTE D’IVOIRE

Abstract

The northwest ofCote d'Ivoire, as most tropical regions has alternating wet and dry periods. In a context climate more and more disrupted by human activities, it is essential to analyze the dry spells at various time scales in order to propose to the people of mitigation and adaptation measures in the field of water management. In this perspective, three stations with longer rainfall series were analyzed. The analysis used the values of the standardized precipitation index calculated for time scales of 5 years, 35 years and 70 years. The results indicate that the most remarkable for their drought intensity, duration and frequency occurred during the period 1970-1999 and regardless of the time scale considered. These dry spells have reached their peaks in 1983 and 1987 with extremely severe droughts type. The stations of Tengrela and Boundiali located north of the study area are most affected by drought. In addition, it analyzes showed that the time scale long-term seems more appropriate to describe with more details the dry spells.