Study of the impact of climate change on water resources in the Prerif mountains (Morocco)

Resumen

Climate change has a significant impact on the availability of water resources; which leads to a disruption of the natural seasonal regimes of watercourses as well as the reduction of the storage capacity at the level of the groundwater and the reservoirs of the dams. Morocco, due to its geographical position within the Mediterranean basin, is one of the countries most vulnerable to climate variability. In the Prérif mountains, climatic and therefore hydrological droughts during the last decades

have had dramatic consequences not only on agricultural yields, but also on the physical and human environment. They have resulted in aridification of these environments, as well as a severe lack of water resources. In terms of the analysis of dry periods, which have a very negative impact on the pre-Rifan environment, it seems quite obvious that the recurrent droughts which have raged in the region since the 1980s are marked by an intensity which essentially shows a cumulative aspect and recurring in very deficient years. They are characterized by very low drought indices. Additionally, monthly dry sequences were detected, notably between 1998 and 2001 with a sequence of 30 dry months and between 2007 and 2008 with a sequence of 24 dry months. Similarly, intercalary absolute droughts during the agricultural year, which were quite frequent at the time, reflect a disruption of seasonal rhythms. Thus, the depletion of water resources throughout the region has resulted in a flagrant reduction in the flow of springs and rivers; even a total drying up of certain sources.

This paper proposes to study, based on the analysis of meteorological and hydrological indicators, the downward trends in rainfall and consequently the flagrant reduction of water resources and its consequences on the physical and human environments of this rifan area. The approach adopted is based on an analysis of rainfall and hydrological data from the various stations in the region (research for trends and cycles) as well as on the use of the Standardized Precipitation Index (SPI) and the analysis of meteorological situations at 500 hPa.