Abstract

In Mediterranean countries, climate change is evident through warming trends that accelerate extreme weather events, such as heat waves, heavy rains, and droughts. This study aims to analyze the spatiotemporal variability of Precipitation (RR), Maximum Temperatures (Tmax), Minimum Temperatures (Tmin), and Evapotranspiration, and to identify significant trends in these hydro-climatic parameters for the Beni Mellal-Khenifra region, Morocco. We assessed the effectiveness of ERA5 (European Centre for Medium-Range Weather Forecasts Reanalysis Version 5) and TerraClimate data from 1983 to 2022 to describe current and projected climatic trends. Our evaluation involved comparing ground and satellite data, using the Person correlation coefficient (r), bias, and root mean square error (RMSE). Statistical techniques such as the Mann-Kendall test were used to detect long-term trends, while the Sen’s Slope method quantified trend magnitudes. We also assessed spatiotemporal variability with interpolations and descriptive statistics. The results show distinct patterns. Precipitation exhibits a decreasing trend, with a maximum decrease of −1.50 in Khouribga. Conversely, Tmax, Tmin, and evapotranspiration show increasing trends. Tmax, for example, reaches a maximum increase of 3.8 in Khouribga, while Tmin and evapotranspiration have maximum increases of 2.5 in Fquih Ben Saleh and 0.8 in Azilal, respectively. Comparing periods D1 (1983–1992) and D4 (2013–2022), Tmax increased by 1.54°C, and Tmin by 1.16°C. Precipitation patterns show fluctuations, with RRmax decreasing from 801.15 mm in D1 to 716.11 mm in D4, while RRmin increased from 280.31 to 295.09 mm. These trends highlight significant changes in the region’s climate, increasing vulnerability and impacting natural resources, especially water.