Characterization and Spatialization of Drought by the Standardized Precipitation Index (SPI) in the Upper Basin of the Oum Er Rbia River
Abstract
The Moroccan climate is characterized by a significant spatial irregularity of precipitation, with a very pronounced contrast between a wet season limited in time and a longer dry season.
The objective of this study is to assess the effects of drought on water resources in the upper basin of Oum ErRbia river upstream Ahmed El Hansali dam (OER-ud). The method used is based on the calculation of Standardised Precipitation Indices (SPI) on different time scales. For this purpose, an analysis of rainfall data was carried out at rainfall stations in the study area and neighbouring areas between 1974-75 / 2016-17.
The mapping of rainfall and SPI is marked by a spatial contrast in rainfall, between two wet periods: 1974-75 / 1979-80 and 2008-09 / 2016-17, and a dry period 1980-81 / 2007-08.