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Climate Change and Water Resources Management in the Ghis-Nekor Watershed (North of Morocco) – A Comprehensive Analysis Using SPI, RDI and DI Indices

Benyoussef Said, Arabi Mourad, El Yousfi Yassine, Cheikh Boumediene Ben, Abdaoui Abdellali, Azirar Maryam, Mechkirrou Latifa, El Ouarghi Hossain, Zegzouti Younes Filali, Ait Boughrous Ali

Ecological Engineering & Environmental Technology

2024

Vol. 25, iss. 2

199--209

Morocco is currently facing significant challenges due to the ever–changing climate, with its critical water sources crucial for agriculture, economy, and daily life being greatly affected. In order to thoroughly understand the impact of climate change on the Ghis–Nekor watershed, an in–depth study spanning 38 years (1978–2016) was conducted. This involved examining the meteorological data from three stations and utilizing advanced indices, such as SPI, RDI, and DI. The findings of this study revealed prominent shifts in precipitation patterns, indicating a vulnerability in the region. While there was a general increase in annual rainfall during the specified time period, a sharp decline was observed post–2008. Further analysis of drought confirmed the presence of persistent dry spells and recurring episodes, highlighting the urgent need for effective water management strategies. These crucial findings must be considered by decision–makers for successful climate adaptation, emphasizing the key role played by this study in mitigating the effects of climate change.

Characterization of Climatic Drought Sequences in the Upper Moulouya Watershed, Morocco

Hachem Abdelaaziz, Mili El-Mostafa, Benbella Bouchra, El Ouardi Hmidou, Mehdaoui Radouan

Ecological Engineering & Environmental Technology

2023

Vol. 24, iss. 2

162--179

Like most of the countries of the African continent and the MENA, Morocco has experienced alternating wet and dry periods for several decades and is still confronted with the effects of unstable climate change due to the specificities conferred by its geographical position and the diversity of its ecosystems. It is one of the countries most affected by desertification, with an arid and semi-arid climate covering more than 93% of its territory. Indeed, the Upper Moulouya watershed has been exposed to severe droughts several times in recent decades. The spatial and temporal distribution of drought episodes in this watershed is studied over a 91-year period between 1931 and 2022. In order to characterize and evaluate the severity and sustainability of drought in this watershed, four indices were used and applied in this study, as they have advantages in terms of statistical consistency and have the capacity to describe, through different time scales (short, medium and long) the impacts of the climatic drought in question. These are the Standardized Precipitation Index SPI, RDI, RI and DI. The annual rainfall series at the eight meteorological stations of the said watershed show irregularities and very marked spatial and temporal variability with a generally decreasing trend. The SPI calculation results obtained show a heterogeneous distribution of SPI values throughout the watershed area. The analysis of the graphical illustrations of this index allowed to highlight an important fluctuation of the dry and wet periods with a strong dominance and tendency to drought with the order of 51% in the stations of Midelt, and Ansegmir, 52% in the station of Zaida, 59% in the stations of Tabouazant, Barrage (Dam) Enjil and El Aouia, 58% in the station of Louggagh, 47% in the station of Anzar Oufounes. The analysis of the results of the of the drought indices RDI, RI and DI at the level of this watershed also made it possible to highlight the existence of numerous drought sequences alternating with other wet sequences and indicates a dominance of dry years, perfectly remarkable during the period 1976-93. The most important dry episode, in number of successive years, was recorded at the Ansegmir station from 1976-89 and the most important rainy episode was recorded at the Midelt station from 1966-76. The years of the 2015-2022 series show an overall persistent decrease in rainfall, thus allowing the installation of a severe drought episode. The trend in the entire watershed is a decrease in rainfall and the installation of mild, moderate and severe drought episodes of varying length and duration.

Numerical analysis of injection and combustion processes endoscopic observations

Wisłocki K., Kozak W.

Journal of KONES

2002

Vol. 9, No. 1-2

283-290

In the paper a new computer program for the numerical analysis of injection and combustion processes video observations in the I.C. engine has been presented. It is a numerical tool called Picture Analysis and Transformation of the Engine Video Observations Pat-EV evaluated at the Poznań University of Technology, Dept. of Internal Combustion Engines. The application of the Pat-EV-program allows an objective, numerical analysis of every pixel of the picture stored in the AVL/Engine Video System 513D. This analysis makes it possible to determine some important parameters of fuel spray in the cylinder like cone angle, spray penetration velocity and its range, fuel mass distribution across the spray and others. For the combustion process observations it would be possible to determine soot luminescence intensity by different hue or saturation values. It could be useful by approximation of charge temperature in some points of the observed region of the combustion chamber. Further interpretation of the parameters of every pixel allows to determine regions of peak temperatures in the combustion chamber, direction and velocity of flame propagation, and main swirl vectors of the charge. Some examples of the Pat-EV-program application for the analysis of fuel spray and of combustion process video-observations have been presented in this paper. Its main feature and new advantage of the video pictures post-processing is the possibility of the parameterisation and quantitative interpretation of the video-sampled pictures of injection and combustion. They could be used for the engine optimal controlling process.