Regional disparities in the beneficial effects of rising CO2 concentrations on crop water productivity

Research output: Contribution to journalArticle


Rising atmospheric CO2 concentrations ([CO2 ]) are expected to enhance photosynthesis and reduce crop water use. However, there is high uncertainty about the global implications of these effects for future crop production and agricultural water requirements under climate change. Here we combine results from networks of field experiments and global crop models to present a spatially explicit global perspective on crop water productivity (CWP, the ratio of crop yield to evapotranspiration) for wheat, maize, rice and soybean under elevated [CO2 ] and associated climate change projected for a high-end greenhouse gas emissions scenario. We find CO2 effects increase global CWP by 10[0;47]%-27[7;37]% (median[interquartile range] across the model ensemble) by the 2080s depending on crop types, with particularly large increases in arid regions (by up to 48[25;56]% for rainfed wheat). If realized in the fields, the effects of elevated [CO2 ] could considerably mitigate global yield losses whilst reducing agricultural consumptive water use (4-17%). We identify regional disparities driven by differences in growing conditions across agro-ecosystems that could have implications for increasing food production without compromising water security. Finally, our results demonstrate the need to expand field experiments and encourage greater consistency in modelling the effects of rising [CO2 ] across crop and hydrological modelling communities.


  • Delphine Deryng
  • Joshua Elliott
  • Christian Folberth
  • Christoph Müller
  • Thomas A M Pugh
  • Kenneth J. Boote
  • Declan Conway
  • Alex C. Ruane
  • Dieter Gerten
  • James W. Jones
  • Nikolay Khabarov
  • Stefan Olin
  • Sibyll Schaphoff
  • Erwin Schmid
  • Hong Yang
  • Cynthia Rosenzweig
External organisations
  • Eawag: Swiss Federal Institute of Aquatic Science and Technology
  • University of Chicago
  • Columbia University
  • University of East Anglia
  • International Institute for Applied Systems Analysis
  • Potsdam Institute for Climate Impact Research
  • Karlsruhe Institute of Technology
  • University of Birmingham
  • University of Florida
  • London School of Economics and Political Science
  • NASA Goddard Institute for Space Studies
  • Humboldt University of Berlin
  • University of Natural Resources and Life Sciences, Vienna
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Climate Research
Original languageEnglish
Pages (from-to)786-790
Number of pages5
JournalNature Climate Change
Issue number8
Publication statusPublished - 2016 Aug 1
Publication categoryResearch