The IPCC climate models predict, for the Maghreb countries, lower rainfall and increased aridity. Current observations in the three countries of central Maghreb (Morocco, Algeria, and Tunisia) are not consistent with these predictions. To demonstrate this new trend, a detailed regional analysis of rainfall evolution is conducted. This investigation is based on the calculation of the reduced centered index and the chronological graphical method of processing information (MGCTI) of “Bertin matrix” type. The results show extreme variability of this parameter and the severe past drought (more intense for Morocco, in which the drastic conditions from the seventies are observed). The results also show the beginning of a gradual return to wetter conditions since the early 2000s in Algeria and Tunisia and from 2008 for Morocco (this trend is confirmed by recent agricultural production data in 2011/2012 and 2012/2013).

This study concerns the West African Sahel. The Sahelian climate is characterized by a long dry season and a rainy season which starts in June and ends in September–October. This latter season is associated with the process of oceanic moisture transfer to the mainland (the West African Monsoon). This movement is governed by an overall moving of the meteorological equator and its low-pressure corridor (Intertropical Convergence Zone, ITCZ) towards the north, under the effect of the attraction of the Saharan thermal depressions and a greater vigor of the anticyclonic nuclei. This study was conducted on 27 Sahelian climatic stations in three countries (Burkina Faso, Mauritania, and Senegal). The method used to determine the modes of this variability and the trends of rainfall is the chronological graphic method of information processing (MGCTI) of the “Bertin Matrix” and continuous wavelets transform (CWT). Results show a rain resumption observed in the recent years over the Sahelian region and a convincing link with the surface temperature of the Atlantic Ocean.

IPCC climate forecast models, applicable to the Maghreb countries (Morocco, Algeria, and Tunisia), predict a decrease in atmospheric precipitation, greater variability, and an increase in aridity. In recent years, the entire region has been experiencing unprecedented climate upheavals. Climatic droughts have become increasingly severe and recurrent (drastically reducing water stocks). We are also witnessing a remarkable increase in temperatures and a greater frequency of heat waves. Faced with these new provisions, this territory (long considered an area of water stress) is now subject to very strong tensions, which have led to a greater demand for water and a decrease in supply. To understand the intensity of this “climate–water” crisis, we propose an analysis of this priority issue based on the evolution of precipitation over more than half a century of records. To determine precipitation trends and define rainfall cycles in these three countries, the graphical chronological method of information processing (MGCTI) of the “BERTIN Matrix” type is used. Annual precipitation totals from 29 stations were used for the MGCTI (chronological graphic method of information processing) for the period 1970–2023. These data come from the national meteorological networks of the National Meteorological Office (ONM) for Algeria, National Institute of Meteorology (NIM) for Tunisia, and National Directorate of Meteorology (DMN) for Morocco, and the from the websites of the National Climatic Data Center (NCDC) and “TuTiempo Network”. Monthly pluviometric totals from three stations, Dar El Beida (Algeria), Casablanca (Morocco), and Tunis (Tunisia), as well as the monthly NAO (North Atlantic Oscillation) and MOI (Mediterranean Oscillation Index) were used for the wavelet coherence method for the period 1970–2022. Data analysis shows that the entire region is subject to four extreme precipitation cycles (dry and wet). The last dry period was remarkably intense and led to a sharp increase in water stress throughout the region. An analysis of monthly precipitation from three stations (Casablanca, Dar El Beida, and Tunis) using the wavelet coherence method also highlighted a close relationship with the “NAO” and “MOI” circulation.

This study is the third in a series of investigations conducted by the authors, and certainly the most comprehensive research regarding the former uranium, copper, and charcoal mines from a particular geographical area of Romania. In this respect, the present scientific incursion focused on two areas containing former extraction uranium ore sites, Ciudanovita and Lisava, as well as copper ore from Moldova Noua and charcoal mines from Anina, Banat Region, Romania. It highlighted that, for the first time, the heavy metal concentration was correlated with the values of physicochemical indicators of water (i.e., EC, DO, pH, resistivity, salinity, and ORP), by using multivariate analysis, to shape a regional based model on spatial distributions and the variability of toxic contaminants from the hydrographic basin of Banat, Romania, as a consequence of former uranium, copper, and charcoal mines. In this regard, 11 metals including Al, Cr, Mn, Fe, Ni, Co, Cu, Zn, Sr, Cd, and Pb from different water samples (well, spring, river, and lake), collected from three mining areas (uranium, copper, and coal mines) were investigated. Non-carcinogenic and carcinogenic health risks of seven heavy metals were assessed using the EDI, DIM, and THQ. The obtained THQ values were within the acceptable limits for cancer risks for adults, but as regards children, eight samples out of 18 proved toxic. However, the HRI and THQ average values for Cd (0.265 adults/0.996 children) and Pb (0.025 adults/0.095 children) for children were 3–4 times higher than those for adults. This is a source of concern as their prevalence in well water exposes children and residents in the Banat Region to the risk of various types of cancers.

The last few decades have recorded a high frequency of the meteorological drought phenomenon. Southern and south-eastern Romania make no exception, with such phenomena often occurring from July to November 2011, which brought about an agrometerological drought that lasted from the third decade of July to early December, with a slight improvement in October. This situation led to a decrease in soil water reserves, mainly in the first 20 cm, with a negative impact on agricultural crops and the following agricultural year as well. The methodology was based on a correlative analysis between the decadal rainfall quantities and the existing soil water reserve, during the interval between June and November 2011, for eight weather stations. The statistico-mathematical data analysis showed an intensification of the pedological drought phenomenon in September, with a slight improvement in October and an increase in November.