What are the Impacts of Global Warming on Rainfall Variability Patterns in the Daoura Watershed (South-East Morocco)?

Abstract

The Daoura watershed (35,000 km2) is part of the great southern pre-Saharan Moroccan half, where aridity is the major handicap and water availability is a precious resource for development. This water constraint is particularly acute in the context of global warming and its impact on regional water resources. Rainfall, as a key climatic element of the water resource, requires a more detailed and precise study in order to identify the possible beginning of such a change and the current rainfall trends. Such an objective required monthly rainfall data recorded on a dozen climate stations and for a period of more than half a century (1957-2018). After a Wong homogeneity test, a Principal Component Analysis, performed on the monthly rainfall variables, is used for the reconstruction of the missing data and for a spatial-temporal regionalization. The scores thus deduced from this regionalization will be used for an analysis of rainfall trends, according to the Man Kendall test, and for an analysis of the beginning of a change according to the Pettitt and Hubert stationarity tests. The results obtained contribute to the implementation of a sustainable management of water resources in a pre-Saharan environment where the oasis resources represent a major issue, strongly threatened by global warming.