This study investigates the impacts of climate change on temperature and precipitation patterns across four governorates in southern Iraq—Basrah,Thi Qar,Al Muthanna,and Messan—using an inte-grated modeling framework...This study investigates the impacts of climate change on temperature and precipitation patterns across four governorates in southern Iraq—Basrah,Thi Qar,Al Muthanna,and Messan—using an inte-grated modeling framework that combines the Long Ashton Research Station Weather Generator(LARS-WG)with three CMIP5-based Global Climate Models(Hadley Centre Global Environmental Model version 2-Earth System(HadGEM2-ES)),European Community Earth-System Model(EC-Earth),and Model for Interdisciplinary Research on Climate version 5(MIROC5).Projections were generated for three future time periods(2021–2040,2041–2060,and 2061–2080)under two Representative Concentration Pathways(RCP4.5 and RCP8.5).By integrating high-resolution climate simulations with localized drought risk analy-sis,this study provides a detailed outlook on climate change trends in the region.The novelty of this research lies in its high-resolution,station-level analysis and its integration of localized statistical downscal-ing techniques to enhance the spatial applicability of coarse GCM outputs.Model calibration and validation 2 were performed using historical climate data(1990–2020),resulting in high accuracy across all stations(R=0.91–0.99;RMSE=0.19–2.78),thus reinforcing the robustness of the projections.Results indicate a significant rise in average annual maximum and minimum temperatures,with increases ranging from 0.88°C to 3.68°C by the end of the century,particularly under the RCP8.5 scenario.Precipitation patterns exhibit pronounced interannual variability,with the highest predicted increases reaching up to 19.26 mm per season,depending on the model and location.These shifts suggest heightened vulnerability to drought and water scarcity,particularly in already arid regions such as Muthanna and Thi Qar.The findings under-score the urgent need for adaptive strategies in water resource management and agricultural planning,providing decision-makers with region-specific climate insights critical for sustainable development under changing climate conditions.展开更多
Rapid growth in energy demand and accompanying hydropower development has been observed in the Lancang-Mekong River Basin(LMRB)in the last two decades.However,climate-induced variations in water resources have brought...Rapid growth in energy demand and accompanying hydropower development has been observed in the Lancang-Mekong River Basin(LMRB)in the last two decades.However,climate-induced variations in water resources have brought uncertainties and challenges to energy security across the LMRB,especially for the hydropower sector.In this study,we propose a multiscale approach by linking two spatially distributed models to simulate and evaluate the effects of climatic drivers both on the water resources and hydropower generations in the LMRB.Specifically,we evaluate the effects of midterm large-scale climatic drivers(i.e.,ENSO)on the local hydrometeorological process and energy production.During ENSO events,the midstream to downstream LMRB is more impacted than the upstream LMRB,leading to hydroelectricity anomalies in the LMRB varying within a range of±11,000GWh.However,basin-wide drought conditions caused by El Niño events in the LMRB do not always result in a reduction in hydropower generation.The proposed approach provides a methodological basis for characterizing power system responses to climatic drivers,potentially informing the future energy strategy and infrastructure development in the LMRB.展开更多
An-Najaf province is situated in south-western part of Iraq. It is 70 meters above the sea level in the dry desert environment. The city is considered as one of the most important cities in Iraq, facing a fast populat...An-Najaf province is situated in south-western part of Iraq. It is 70 meters above the sea level in the dry desert environment. The city is considered as one of the most important cities in Iraq, facing a fast population growth and continuous development in constructions such as residential complexes, hotels, bridges and shopping malls. Soil investigation data for An-Najaf Province (An-Najaf and Kufa cities) from 464 boreholes drilled by the Na-tional Centre for Construction Laboratories & Researches (NCCLR)/Babylon laboratory were used in this research. The data were analysed and possessed using Excel program then represented on the Geographical Information System (GIS) program by Inverse Distance Weighted (IDW) tool to create an allowable bearing capacity map for the soil at depths 0 - 2 meters. The allowable bearing capacity is one of the most important soil characteristics to be considered when making a database for An-Najaf city soil. Geographical Information System GIS program enables to create reliable database for any characteristic and it is one of the best programs to produce an accurate map and allow ease in dealing with it. Those maps cover all the studied areas and by using contour lines, approximate values for no-data areas can be obtained. The results show that the allowable bearing capacity range is 5 - 20 Ton/m2 for both An-Najaf and Kufa cities. Kufa city has the range 5 - 9 Ton/m2. An-Najaf city has the range 7 - 18 at the center, 8 - 10 Ton/m2 at the north eastern part, 7 - 14 Ton/m2 for the north western part, 6 - 12 Ton/m2 at the south eastern and 12 - 19 Ton/m2 at the south western.展开更多
Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction. The case with a single tall sill was simulated ...Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction. The case with a single tall sill was simulated in a horizontal flume downstream of a sluice gate. Results of experiments are compared with the classical hydraulic jump, and significant effect of tall sill on dissipation of energy in shorter distance was confirmed. Furthermore, the generated jumps were classified based on the ratio of sill height to basin length, and a simple design criterion was proposed to estimate the basin length for a desired jump and particular inflow.展开更多
In this work, we studied the dimensions of stream tube in the vertical as well as inclined bank conditions. Data were collected from both a physical model and a 3-D numerical model（SSIIM 2）. Equations for predicting...In this work, we studied the dimensions of stream tube in the vertical as well as inclined bank conditions. Data were collected from both a physical model and a 3-D numerical model（SSIIM 2）. Equations for predicting stream tube dimensions were presented and compared with existing formulae. In comparison with vertical bank, it is found that inclining bank causes the bottom stream tube width to be greater than at the surface. The strength of secondary current formed at the entrance of branch channel is reduced. These changes in flow pattern can reduce the amount of sediment delivery into the intake.展开更多
文摘This study investigates the impacts of climate change on temperature and precipitation patterns across four governorates in southern Iraq—Basrah,Thi Qar,Al Muthanna,and Messan—using an inte-grated modeling framework that combines the Long Ashton Research Station Weather Generator(LARS-WG)with three CMIP5-based Global Climate Models(Hadley Centre Global Environmental Model version 2-Earth System(HadGEM2-ES)),European Community Earth-System Model(EC-Earth),and Model for Interdisciplinary Research on Climate version 5(MIROC5).Projections were generated for three future time periods(2021–2040,2041–2060,and 2061–2080)under two Representative Concentration Pathways(RCP4.5 and RCP8.5).By integrating high-resolution climate simulations with localized drought risk analy-sis,this study provides a detailed outlook on climate change trends in the region.The novelty of this research lies in its high-resolution,station-level analysis and its integration of localized statistical downscal-ing techniques to enhance the spatial applicability of coarse GCM outputs.Model calibration and validation 2 were performed using historical climate data(1990–2020),resulting in high accuracy across all stations(R=0.91–0.99;RMSE=0.19–2.78),thus reinforcing the robustness of the projections.Results indicate a significant rise in average annual maximum and minimum temperatures,with increases ranging from 0.88°C to 3.68°C by the end of the century,particularly under the RCP8.5 scenario.Precipitation patterns exhibit pronounced interannual variability,with the highest predicted increases reaching up to 19.26 mm per season,depending on the model and location.These shifts suggest heightened vulnerability to drought and water scarcity,particularly in already arid regions such as Muthanna and Thi Qar.The findings under-score the urgent need for adaptive strategies in water resource management and agricultural planning,providing decision-makers with region-specific climate insights critical for sustainable development under changing climate conditions.
基金funded by the National Natural Science Foundation of China(92047302 and U2243215).
文摘Rapid growth in energy demand and accompanying hydropower development has been observed in the Lancang-Mekong River Basin(LMRB)in the last two decades.However,climate-induced variations in water resources have brought uncertainties and challenges to energy security across the LMRB,especially for the hydropower sector.In this study,we propose a multiscale approach by linking two spatially distributed models to simulate and evaluate the effects of climatic drivers both on the water resources and hydropower generations in the LMRB.Specifically,we evaluate the effects of midterm large-scale climatic drivers(i.e.,ENSO)on the local hydrometeorological process and energy production.During ENSO events,the midstream to downstream LMRB is more impacted than the upstream LMRB,leading to hydroelectricity anomalies in the LMRB varying within a range of±11,000GWh.However,basin-wide drought conditions caused by El Niño events in the LMRB do not always result in a reduction in hydropower generation.The proposed approach provides a methodological basis for characterizing power system responses to climatic drivers,potentially informing the future energy strategy and infrastructure development in the LMRB.
文摘An-Najaf province is situated in south-western part of Iraq. It is 70 meters above the sea level in the dry desert environment. The city is considered as one of the most important cities in Iraq, facing a fast population growth and continuous development in constructions such as residential complexes, hotels, bridges and shopping malls. Soil investigation data for An-Najaf Province (An-Najaf and Kufa cities) from 464 boreholes drilled by the Na-tional Centre for Construction Laboratories & Researches (NCCLR)/Babylon laboratory were used in this research. The data were analysed and possessed using Excel program then represented on the Geographical Information System (GIS) program by Inverse Distance Weighted (IDW) tool to create an allowable bearing capacity map for the soil at depths 0 - 2 meters. The allowable bearing capacity is one of the most important soil characteristics to be considered when making a database for An-Najaf city soil. Geographical Information System GIS program enables to create reliable database for any characteristic and it is one of the best programs to produce an accurate map and allow ease in dealing with it. Those maps cover all the studied areas and by using contour lines, approximate values for no-data areas can be obtained. The results show that the allowable bearing capacity range is 5 - 20 Ton/m2 for both An-Najaf and Kufa cities. Kufa city has the range 5 - 9 Ton/m2. An-Najaf city has the range 7 - 18 at the center, 8 - 10 Ton/m2 at the north eastern part, 7 - 14 Ton/m2 for the north western part, 6 - 12 Ton/m2 at the south eastern and 12 - 19 Ton/m2 at the south western.
基金the Chamran University of Ahwaz,Jundishapur University of Technology,and the Centre of Shahid Excellence on Operation Management of Irrigation and Drainage Networks for financial support and facilitation of the experiments
文摘Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction. The case with a single tall sill was simulated in a horizontal flume downstream of a sluice gate. Results of experiments are compared with the classical hydraulic jump, and significant effect of tall sill on dissipation of energy in shorter distance was confirmed. Furthermore, the generated jumps were classified based on the ratio of sill height to basin length, and a simple design criterion was proposed to estimate the basin length for a desired jump and particular inflow.
文摘In this work, we studied the dimensions of stream tube in the vertical as well as inclined bank conditions. Data were collected from both a physical model and a 3-D numerical model（SSIIM 2）. Equations for predicting stream tube dimensions were presented and compared with existing formulae. In comparison with vertical bank, it is found that inclining bank causes the bottom stream tube width to be greater than at the surface. The strength of secondary current formed at the entrance of branch channel is reduced. These changes in flow pattern can reduce the amount of sediment delivery into the intake.
