Forecasting the Water Supply and Utilization in China Using Grey Model

Grey Models are employed for simulating and forecasting the overall water supply in China, as well as a range of water uses for agriculture, industry, human consumption and ecological protection. Parameter optimization of a GM(1,1) model is formulated as a combinatorial optimization problem and is solved collectively using LINGO (a software of Operational Research). The annual data from 2001 to 2007 are used for estimating the model parameters. The data for 2008 are also included for the purpose of comparing the forecasted values to the measured observations to demonstrate the model's ability to forecast. Comparison of the simulation and forecasting results of the optimal GM(1,1) model with those of the traditional one demonstrates that the optimal algorithm is a good alternative for parameter optimization of a GM(1,1) model. The optimal GM(1,1) model is used to forecast the annual values of the various time series for the period from 2009 to 2011 based on the data from 2001 to 2008. The modeling results can assist the government in developing future policies regarding water resources management.