Global Agricultural Green and Blue Water Consumption Under Future Climate and Land Use Changes

TitleGlobal Agricultural Green and Blue Water Consumption Under Future Climate and Land Use Changes
Publication TypeJournal Article
Year of Publication2019
JournalJournal of Hydrology
Volume574
Pages242-256
Date Published04/2019
Abstract / Summary

Agriculture accounts for 90% of global freshwater consumption and it is expected to intensify in the future. Climate and land use changes are two major factors affecting crop green and blue water consumption, and in this study we explicitly consider the effects of both factors in a consistent modeling framework. Two important research questions are addressed: 1) How will global crop green and blue water consumption evolve over the 21st century under climate and land use changes; and 2) what are the individual and combined effects of climate and land use changes on future crop green and blue water consumption? To tackle these two questions, a crop water use module is developed based on the Global Change Assessment Model (GCAM) and its hydrology module (i.e., Xanthos). Crop specific green and blue water consumption are then calculated at global 0.5° × 0.5° grid scale. Results show that global crop green water consumption increases by 12% in 2090s when compared with that in 1971–2000, and climate change dominates over land use change in determining the trend of global crop green water consumption. However, expansion in global irrigated area dominates the changing trend of global crop blue water consumption which increases 70% by 2090s, especially in regions with significant irrigated land expansion (e.g. northern Africa, central Asia, China, Mexico, the Middle East, Russia, southern Asia, and Argentina). Furthermore, global crop blue water dependence will increase under climate and land use changes, especially in arid regions.

URLhttps://linkinghub.elsevier.com/retrieve/pii/S002216941930383
DOI10.1016/j.jhydrol.2019.04.046
Funding Program: 
Journal: Journal of Hydrology
Year of Publication: 2019
Volume: 574
Pages: 242-256
Date Published: 04/2019

Agriculture accounts for 90% of global freshwater consumption and it is expected to intensify in the future. Climate and land use changes are two major factors affecting crop green and blue water consumption, and in this study we explicitly consider the effects of both factors in a consistent modeling framework. Two important research questions are addressed: 1) How will global crop green and blue water consumption evolve over the 21st century under climate and land use changes; and 2) what are the individual and combined effects of climate and land use changes on future crop green and blue water consumption? To tackle these two questions, a crop water use module is developed based on the Global Change Assessment Model (GCAM) and its hydrology module (i.e., Xanthos). Crop specific green and blue water consumption are then calculated at global 0.5° × 0.5° grid scale. Results show that global crop green water consumption increases by 12% in 2090s when compared with that in 1971–2000, and climate change dominates over land use change in determining the trend of global crop green water consumption. However, expansion in global irrigated area dominates the changing trend of global crop blue water consumption which increases 70% by 2090s, especially in regions with significant irrigated land expansion (e.g. northern Africa, central Asia, China, Mexico, the Middle East, Russia, southern Asia, and Argentina). Furthermore, global crop blue water dependence will increase under climate and land use changes, especially in arid regions.

DOI: 10.1016/j.jhydrol.2019.04.046
Citation:
Huang, Z, M Hejazi, Q Tang, CR Vernon, Y Liu, M Chen, and K Calvin.  2019.  "Global Agricultural Green and Blue Water Consumption Under Future Climate and Land Use Changes."  Journal of Hydrology 574: 242-256.  https://doi.org/10.1016/j.jhydrol.2019.04.046.