Multsch SKrol MSPahlow MAssunção ALCBarretto AGOPde Jong van Lier QBreuer L2020-01-212020-01-212019Multsch S, Krol MS, Pahlow M, Assunção ALC, Barretto AGOP, de Jong van Lier Q, Breuer L Assessment of potential implications of agricultural irrigation policy on surface water scarcity in Brazil. Hydrology and Earth System Sciences Discussions. 1-28.1812-2116http://hdl.handle.net/10092/17876Expanding irrigated cropping areas is one of Brazil’s strategies to increase agricultural production. This expansion is constrained by water policy goals to restrict water scarcity to acceptable levels. We therefore analysed the trade-off between levels of acceptable water scarcity, and feasible expansion of irrigation. The appropriateness of water use in agricultural production was assessed in categories ranging from excellent to very critical based on the river flow that is equalled or exceeded for 95% of the time (Q95) as indicator for physical water availability. The crop water balance components were determined for 166,842 sub-catchments covering all of Brazil. The crops considered were cotton, rice, sugarcane, beans, cassava, corn, soybean and wheat, together accounting for 96% of the harvested area of irrigated and rainfed agriculture. On currently irrigated land irrigation must be discontinued on 53.6% (2.30 Mha) for an excellent water scarcity level, on 44.5% (1.91 Mha) for a comfortable water scarcity level and on 35.2% (1.51 Mha) for a worrying water scarcity level, in order to avoid critical water scarcity. An expansion of irrigated areas by irrigating all 45.56 Mha of rainfed area would strongly impact surface water resources, resulting in 26.02 Mha experiencing critical and very critical water scarcity. The results show in a spatially differentiated manner that potential future decisions regarding expanding irrigated cropping areas in Brazil must, while pursuing to intensify production practices, consider the likely regional effects on water scarcity levels, in order to reach sustainable agricultural production.enManuscript under review for journal Hydrol. Earth Syst. Sci. This is just a preview and not the published paper. c Author(s) 2019. CC BY 4.0 License.Journal Article2019-06-14Field of Research::09 - Engineering::0905 - Civil Engineering::090509 - Water Resources EngineeringFields of Research::41 - Environmental sciences::4104 - Environmental management::410406 - Natural resource managementFields of Research::44 - Human society::4407 - Policy and administration::440704 - Environment policyhttps://doi.org/10.5194/hess-2019-174