ABSTRACT
Climate change is a challenging issue of the recent years. Climate change will affect all components of human life because it affects all natural systems including the hydrologic cycle. Climate change will accelerate the hydrologic cycle and will intensify extreme events such as flood and droughts. Regarding the high population density in urban areas and the considerable water demand in these regions, urban water deficit is a common problem throughout the world especially in arid and semiarid regions. Climate change impacts could result in intensifying water shortage in the urban area. The water demand would increase because of global warming, while the water resources perhaps would be more limited as different studies show. In this chapter, first, the climate change impact on different components of the hydrologic cycle in the urban area is investigated. Then is discussed how climate change can effect urban water deficit through analyzing the climate change impact on water demand and water resources in the urban area. Urban water resources planning and management under climate change impacts and water supply reliability are the next issues discussed in this chapter. A case study on urban water supply reliability analysis under climate change impacts is also provided for more clarification. The investigations show that urban water deficit is intensifying under climate change impacts and the reliability of urban water supply systems is decreasing. New approaches should be considered in dealing with this issue such as more emphasis on demand management, increasing efficiency of water usage, and water reuse and recycling.
