Development and testing of the WaterGAP 2 global model of water use and availability

Abstract Growing interest in global environmental issues has led to the need for global and regional assessment of water resources. A global water assessment model called “WaterGAP 2” is described, which consists of two main components'a Global Water Use model and a Global Hydrology model. These components are used to compute water use and availability on the river basin level. The Global Water Use model consists of (a) domestic and industry sectors which take into account the effect of structural and technological changes on water use, and (b) an agriculture sector which accounts especially for the effect of climate on irrigation water requirements. The Global Hydrology model calculates surface runoff and…