New Paper from IFPRI: Implications for food and agricultural policy of "green" and "blue" water accounting

By Timothy B. Sulser, Claudia Ringler, Tingju Zhu, Siwa Msangi, Elizabeth Bryan, and Mark W. Rosegrant

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Globally, most food is produced using soil moisture that comes from precipitation (i.e., "green" water). Moreover, most of the water that reaches plants in irrigated systems also stems from precipitation. Despite this, irrigation (or "blue") water has typically been the focus for policy analysis. This paper analyzes alternative water futures using a combined green and blue water accounting framework embedded within the water simulation components of IFPRI's International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT).

The results reveal that accounting explicitly for green water resources broadens the scope of options for decision-makers who are seeking to improve agricultural production in the face of rising food and energy prices, a degrading water and land resource base, and increasing demands. This analysis highlight the importance of green/blue water accounting and presents a wider range of agricultural science and technology policy options for increasing global crop productivity across a span of potential futures.