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Flood and drought are natural phenomena whose probability of occurrence increases with changing weather conditions. Climate change has affected the hydrologic cycle's parameters and led to changes in temperature and precipitation pattern, which may increase the probability of occurrence of floods and droughts. Arid and semi‐arid areas are subject to extreme weather conditions and water resources scarcity. This study aims to assess drought and flood in Syria using remote sensing data. Monthly precipitation data have been collected from 10 land stations in the western part of Syria for the period (1991–2009) and satellite images for monthly precipitation from 1983 to 2020 were collected. The land stations data were used to correct the satellite images and correction equation was developed for each station. Standardized Precipitation Index (SPI) is used for analysis of drought and flood. Also, the main parameters for drought and flood, severity, intensity, duration, and the average return time were estimated. The results showed extreme flood events were recorded in 1988, 2002, 2012, and 2019 and extreme drought events were recorded in 1990, 2014, and 2016. The highest severity of drought and flood were recorded in 2014 and 1988 respectively. However, the highest intensity of droughts and floods was recorded in 2016 and 1988, respectively. If land station data are unavailable, as in the case of Syria owing to the protracted war, satellite images may be a useful source of data for drought and flood analysis after correction. This methodology can help in drought/flood analysis and estimate severity, intensity, duration, and the average return time of flood and drought in other locations of the world. The results proved that SPI is a useful tool to predict the time of occurrence of both flood and drought that could help decision‐makers for putting efficient plans for flood and drought risk management that could mitigate the impacts of such risks. [ABSTRACT FROM AUTHOR]

Understanding and modeling a dam breaching process is an essential investigation, because it aims to minimize the flood's hazards, and its impact on people and structures, using suitable mitigation plans. In the current study, three-dimensional numerical modeling is carried out using the FLOW-3D HYDRO program to investigate the impact of various factors, including the dam grain size materials, crest width, inflow discharge, and tail water depth on the dam breach process, particularly the peak outflow, and the erosion rate. The results show that changing the grain size of the dam material from fine sand to medium and coarse sand leads to an increase in the peak outflow discharge by 16.0% and the maximum erosion rate by 20.0%. Furthermore, increasing the dam crest width by 40% leads to a decrease in the peak outflow by 3.0% and the maximum erosion rates by 4.50%. Moreover, increasing the inflow discharge by 25.0% increases the peak outflow by 23.0% and the maximum erosion rates by 21.0%. Finally, increasing the tail water depth by 50.0% leads to decreasing the peak outflow by 4.50% and the maximum erosion rate by 43.0%. The study findings are considered of high importance for dam design and operation control. Moreover, the results can be applied for the optimum determination of the crest width and tail water depth that leads to improving the dam stability. [ABSTRACT FROM AUTHOR]

The paper explores the occurrence of minimal precipitation extremes at specific meteorological stations in the southeastern region of Serbia. With climate change leading to increased instances of droughts, these natural phenomena have garnered heightened interest due to their negative impacts on society, environment, and the economy. Employing the SPI-12 index in the southeastern part of Serbia from 1946 to 2021, the study sheds light on the vulnerability of this natural phenomenon in the observed stations. Understanding historical manifestation of these events helps water resource managers, farmers and policymakers manage these risks in the southeastern region of Serbia. [ABSTRACT FROM AUTHOR]

Coastal areas are increasingly endangered by climate change and associated sea level rise, which could have serious consequences, such as shoreline erosion and coastal city submergence. The current study aims to conduct a historical trend analysis (HTA) and predict the shoreline changes of the Nile Delta coasts. The Digital Shoreline Analysis System (DSAS) software, with the GIS environment, is used for monitoring the shoreline changes using a number of statistical methods (SCE, NSM, EPR, WLR and LRR). Satellite images from 1974 to 2022 were collected and geometrically corrected using supervised classification to detect the shoreline change of the Nile Delta. The GIS was used for detecting and monitoring changes in the shoreline, as well as forecasting future changes in the shoreline for the next 10 and 20 years (2033–2043). The critical sections of the Nile Delta were identified, and a time series analysis of shoreline changes was conducted. For each section, linear equations were established to predict probable changes in the shoreline. Between 1974 and 2022, the shoreline of the Nile Delta moved inland in different directions due to coastal erosion, and predictions indicate that this erosion will continue until both 2033 and 2043, particularly affecting the Rosetta and Damietta sections. The erosion rate ranged between 30–60 and 10–25 m/year at Rosetta and Damietta, respectively, but at Manzala, it ranged between 8–15 m/year. Continued erosion of the Nile Delta shoreline could have severe consequences that could affect the inhabitants, economy, buildings, roads, railways, and ports. These areas need an integrated coastal management strategy which incorporates increasing consciousness, urban development, and the implementation of rules and adaptation plans. The results of the current study and forecasting the shoreline change could help in protecting such areas. [ABSTRACT FROM AUTHOR]