الفهرس 
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Abstract
During the twentieth century, the intensity and frequency of extreme events (e.g., storms and floods) have significantly altered globally due to human-induced climate change. Recently, it has been recognized that some regions in Egypt have exposed to extreme rainfall events which led in some cases to severe flash floods. This study is divided into two main parts. In the first part, the variability of rainfall characteristics in Egypt was investigated based on a detailed statistical analysis of historical rainfall records at 31 stations. Both parametric (Pearson) and non-parametric (Mann–Kendall and Spearman) tests were applied on annual, seasonal, and monthly precipitation indices to examine temporal trends. A classification of significant trends was introduced to assess the degrees of their likelihood. The results detected significant trends in annual indices: maximum precipitation, total precipitation, simple daily intensity index, and number of rainy days at 29, 19, 19, and 13% of stations, respectively. Significant trends in seasonal and monthly indices were also found at a few stations. For all indices, 76% of the detected significant trends are negative concluding a decrease in the amount of precipitation in Egypt. Additionally, only 5% of the detected trends are classified as less likely, while the rest is likely and extremely likely, indicating a high probability of most detected trends. Generally, the detected trends do not form any spatial pattern in all cases. The second part adopted a methodology to analyze precipitation projections over Egypt in the context of climate change. The rainfall simulations with a grid space of 0.44̊ (approx. 50 KM× 50 KM), generated by the Regional Climate Model (RCM) labeled (RCA4/ESM-LR), available from the CORDEX framework, were used. Three bias correction methods were applied to adjust the RCM outputs: linear scaling (LS), local intensity scaling (LOCI), and empirical quantile mapping (EQM). The results revealed that the performance of EQM was the best, followed by the LS. Consequently, EQM was used to correct the projection of four annual precipitation indices (AMP, ATP, ANRD, and SDII) under three climate scenarios (RCP 2.6, RCP 4.5, and RCP 8.5). The temporal and spatial changes in the projected rainfall were analyzed by comparing the adjusted RCM projected data for three different periods of the century, represent the near (2020-2030), mid (2060-2070), and far (2090-2100) future, with that of the observed rainfall (2004-2014). The projected changes in AMP, ATP, and ANRD showed significant increases under the three considered RCPs; however, negative changes were detected in few separated locations in the country. The expected increase in rainfall quantity would be accompanied by a more increase in the number of rainy days, resulting in a decrease in SDII. The changes will not be uniformly distributed throughout the century and their magnitudes will be regionally dependent and varied also according to the applied scenario. The results also provided a preliminary impression on the likely impacts of climate change on rainfall characteristics in Egypt.