The proposed project will examine the growing constraints on agricultural water demand. From increasing urbanization to climate change, a number of factors are leading to reductions in the amount of water available for irrigated agriculture. Understanding how agricultural production will change in response to these constraints is critical to studying agricultural policies and to understanding the impacts of a climate change.

We will seek to identify the impacts of competing demands and climate change on agricultural water availability, considering trends in agricultural productivity and irrigation demand with a focus on regions of emerging agricultural water scarcity. Applying the simulation models utilized by the MIT Joint Program on the Science and Policy of Global Change, we will develop and provide data and analysis of agricultural water availability under climate change scenarios. 

The data will be global in scope and include projections of key climatological and hydrologic variables (such as mean annual runoff) for a suite of regions. Projections of agricultural water withdrawals will be included. Simulations based on two Global Climate Models will provide projections to year 2050. A second data set of fine-scale data (99 regions) covering the U.S. will be included to demonstrate the ability of the models to provide greater geographic resolution. A detailed calibration of the global data will be conducted for a selected region, to be determined, that corresponds with other USDA-ERS research (e.g., Egypt, Turkey, or India).