Potential Climate Change Impacts on Water Resources in Egypt

In order to solve the problem that the existing optimal operation model of reservoirs cannot coordinate the contradiction between long-term and short-term benefits, the paper nested the long-term optimal operation and mid-long-term optimal operations of reservoirs and established the multi-objective optimal operation nested model of reservoirs. At the same time, based on this model, the optimal control mode is determined when there are errors in the predicted runoff. In the optimal scheduling nested model, the dynamic programming algorithm is used to determine the long-term optimal scheduling solution, and the genetic algorithm is used to solve the mid-long-term optimal scheduling. The optimal control mode is determined by three indicators: power generation benefit, water level over limit risk rate and the not-exploited water volume. The results show that, on the premise of meeting the flood control objectives, the nested model optimal dispatching plan has higher benefits than the long-term optimal dispatching plan and the actual dispatching plan, which verifies the superiority of the nested model in the reservoir optimal dispatching problem. When there is error in predicting runoff, among the water level control mode, flow control mode and output control mode, the average power generation benefit of output control mode is 150.05 GW·h, the low-risk rate of water level overrun is 0.29, and the not-exploited water volume is 39,270 m3. Compared with the water level control mode and the flow control mode, the output control mode has the advantages of higher power generation efficiency, lower water level over limit risk rate and less not-exploited water volume. Therefore, from the perspective of economic benefit and risk balance, the output control mode in the optimization scheduling nested mode is the optimal control mode.

Section: Constraint Conditionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Research on Reservoir Optimal Operation Based on Long-Term and Mid-Long-Term Nested Models

Zhao

Ruan

et al. 2022

“…Water resources are indispensable natural resources in production and human life as well as other social activities. Factors of climate change, ecological environment evolution and human activities, and climate change and its impact on water resources affect water resources and are important subjects worldwide [1,2]. In the past century, the characteristics of climate and environment have undergone significant changes, such as global warming, and climate change necessarily leads to changes in the hydrological cycle and the spatiotemporal redistribution of water resources [3,4].…”

Section: Introductionmentioning

confidence: 99%

Variation Characteristics of Summer Water Vapor Budget and Its Relationship with the Precipitation over the Sichuan Basin

Zhou

2021

Based on the daily precipitation data from the meteorological stations in Sichuan and the monthly average ERA-Interim reanalysis data from 1979 to 2016, the variation characteristics of summer water vapor budget in the Sichuan Basin and its relationship with precipitation are discussed in this study. The results show that, in summer, the water vapor in the Sichuan Basin and its four sub-basins flows in from the southern and western boundaries and flows out through the eastern and northern boundaries, and the basin is obviously a water vapor sink. From 1979 to 2016, the water vapor inflow from the southern and western boundaries significantly decreased, as well as the water vapor outflow through the eastern boundary. The summer precipitation in the Sichuan Basin is significantly positively correlated with the water vapor inflow at the southern boundary and net water vapor budget of the basin in the same period, and it is negatively correlated with the water vapor outflow at the northern boundary. The southern and northern boundaries are the two most important boundaries for the summer precipitation in the Sichuan Basin. Additionally, this study reveals that, under the multi-scale topography on the east side of the Tibet Plateau, the spatio-temporal distribution of precipitation in the Sichuan Basin results from the interactions between the unique topography of the Sichuan Basin and the different modes of water-vapor transport from low latitudes. The atmospheric circulation over the key area of air–sea interaction in the tropical region and its accompanying systems, as well as the anomalies of regional circulations and water vapor transport over the eastern China and Sichuan Basin, are the main reasons for the variation in summer precipitation in the Sichuan Basin.

“…The pressure on water resources is increasingly heavier and frequently contributes to a decline in available water resources [1]. This phenomenon is particularly visible in arid and semiarid zones, and in the Mediterranean region [2][3][4][5][6]. European countries situated in the temperate climate zone are experiencing problems with water intended for human consumption more frequently.…”

Section: Introductionmentioning

confidence: 99%

The Identification of Risks for Drinking Water Intakes in Urbanized Area: The Case Study of Toruń (Central Poland)

Kubiak-Wójcicka

Jamorska

Górski³

2021

This article discusses the problem of natural hazards connected with climatic changes and their influence on water safety. A medium-sized town in central Poland which is supplied with consumption water from both underground water intakes and surface water resources was selected as a case study. Natural hazards, such as droughts or floods, were identified and the risk of the occurrence of natural hazards concerning water supply systems assessed. The findings of the archived data analysis for the period 1971–2020 helped to identify extreme circumstances, the occurrence of which had an impact on secure water supplies in terms of quantity. Moreover, the results obtained indicate that the greatest influence had all the situations connected with the Drwęca low water discharge, which in the long term could lead to temporary water shortages. In the analyzed period, there was a significant increase in the number of days without precipitation, together with a statistically significant increase in the average annual air temperature. Meteorological hazards related to days without precipitation far outweighed the occurrence of days with intense precipitation. The analysis of water table fluctuations observed at the Jedwabno infiltration intake showed a high sensitivity of the aquifer to atmospheric conditions.