Analysis of meteorological and hydrological drought based in SPI and SDI index in the Inaouen Basin (Northern Morocco)

Drought is a normal climatic feature, which affects almost all regions. It has become in recent years more intense and frequent, which has a very negative impact on the socioeconomic balance of the countries. Among droughts receiving particular interest are meteorological and hydrological droughts. This paper focuses on the analysis of the characteristics of these two types of droughts in the Inaouen region of northern Morocco for different time scales (3, 6 and 12 months). Analysis of the characteristics of meteorological and hydrological drought was assessed using the Standardized Precipitation Index (SPI) and the StreamflowDrought Index (SDI), respectively. The analysis of the trend was based on the test of Mann-Kendall (MK) and regression quantile method. The relationship between SPI and SDI has been apprehended through to the coefficients of correlation of Pearson and Spearman. The results showed that the frequency of episodes of drought varied according the time scale considered. The quantile regression reveals, compared to Mk test, a positive trend at higher quantiles and negative trend at the lower quantiles. Correlation results showed that for the 12-month scale, there is a strong positive correlation between SPI and SDI at different periods. These results provide an overview of drought trends in the region and therefore would be very useful in applying drought adaptation policies by water resource managers.