Water competition between cities and agriculture driven by climate change and urban growth

Abstract

Urban water demand will increase by 80% by 2050, while climate change will alter the timing and distribution of water. Here we quantify the magnitude of these twin challenges to urban water security, combining a dataset of urban water sources of 482 of the world’s largest cities with estimates of future water demand, based on the Intergovernmental Panel on Climate Change (IPCC)’s Fifth Assessment scenarios, and predictions of future water availability, using the WaterGAP3 modelling framework. We project an urban surface-water deficit of 1,3866,764 million m³. More than 27% of cities studied, containing 233 million people, will have water demands that exceed surface-water availability. An additional 19% of cities, which are dependent on surface-water transfers, have a high potential for conflict between the urban and agricultural sectors, since both sectors cannot obtain their estimated future water demands. In 80% of these high-conflict watersheds, improvements in agricultural water-use efficiency could free up enough water for urban use. Investments in improving agricultural water use could thus serve as an important global change adaptation strategy.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Schematic illustration of the methods adopted in this study
Fig. 2: Global urban water security (n = 482).
Fig. 3: Urban surface-water deficit by subregion for the baseline and 2050s.
Fig. 4: Cities and subbasins where an improvement in irrigation water-use efficiency could help to overcome urban surface-water deficits in the future.
Fig. 5: Top 20 cities under urban surface-water deficit affected by climate change and socio-economic development (including urbanization).

References

  1. 1.

    UNDP. World Urbanization Prospects: The 2014 Revision (United Nations Population Division, New York, 2014).

    Google Scholar 

  2. 2.

    Jiang, L. & O’Neill, B. C. Global urbanization projections for the shared socioeconomic pathways. Glob. Environ. Change 42, 193–199 (2017).

    Article  Google Scholar 

  3. 3.

    Flörke, M. et al. Domestic and industrial water uses of the past 60 years as a mirror of socio-economic development: a global simulation study. Glob. Environ. Change 23, 144–156 (2013).

    Article  Google Scholar 

  4. 4.

    Richter, B. D. et al. Tapped out: how can cities secure their water future? Water Policy 15, 335–363 (2013).

    Article  Google Scholar 

  5. 5.

    Amarasinghe, U. & Smakhtin, V. Global Water Demand Projections: Past, Present, and Future (IWMI, Colombo, 2014).

    Google Scholar 

  6. 6.

    Wada, Y. et al. Modeling global water use for the 21st century: the Water Futures and Solutions (WFaS) initiative and its approaches. Geosci. Model Dev. 9, 175–222 (2016).

    Article  Google Scholar 

  7. 7.

    McDonald, R. I. et al. Water on an urban planet: urbanization and the reach of urban water infrastructure. Glob. Environ. Change 27, 96–105 (2014).

    Article  Google Scholar 

  8. 8.

    Li, E., Endter-Wada, J. & Li, S. Characterizing and contextualizing the water challenges of megacities. J. Am. Water Resour. Assoc. 51, 589–613 (2015).

    Article  Google Scholar 

  9. 9.

    Hallegatte, S., Green, C., Nicholls, R. J. & Corfee-Morlot, J. Future flood losses in major coastal cities. Nat. Clim. Change 3, 802–806 (2013).

    Article  Google Scholar 

  10. 10.

    McDonald, R. I. et al. Global urban growth and the geography of water availability, quality, and delivery. AMBIO 40, 437–446 (2011).

    Article  Google Scholar 

  11. 11.

    Revi, A. et al. in Climate Change 2014: Impacts, Adaptation, and Vulnerability (eds Field, C. B. et al.) 535–612 (Cambridge Univ. Press, Cambridge, 2014).

  12. 12.

    Collins, M. et al. in Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) 1062–1087 (Cambridge Univ. Press, Cambridge, 2013).

  13. 13.

    Hanasaki, N. et al. A global water scarcity assessment under shared socio-economic pathway — Part 2: water availability and scarcity. Hydrol. Earth Syst. Sci. 17, 2393–2413 (2013).

    Article  Google Scholar 

  14. 14.

    Wada, Y., Gleeson, T. & Esnault, L. Wedge approach to water stress. Nat. Geosci. 7, 615–617 (2014).

    CAS  Article  Google Scholar 

  15. 15.

    Engel, K., Jockiel, D., Kraljevic, A., Geiger, M. & Smith, K. Big Cities. Big Waters. Big Challenges. Water in an Urbanizing World (WWF, Berlin, 2011).

    Google Scholar 

  16. 16.

    Padowski, J. C. & Gorelick, S. M. Corrigendum: global analysis of urban surface water supply and vulnerability (2014 Environ. Res. Lett. 9, 104004). Environ. Res. Lett. 9, 119501 (2014).

    Article  Google Scholar 

  17. 17.

    Moss, R. H. et al. The next generation of scenarios for climate change research and assessment. Nature 463, 747–756 (2010).

    CAS  Article  Google Scholar 

  18. 18.

    van Vuuren, D. P. et al. A new scenario framework for climate change research: scenario matrix architecture. Clim. Change 122, 373–386 (2014).

    Article  Google Scholar 

  19. 19.

    van Vuuren, D. P. & Carter, T. R. Climate and socio-economic scenarios for climate change research and assessment: reconciling the new with the old. Clim. Change 122, 415–429 (2014).

    Article  Google Scholar 

  20. 20.

    Wimmer, F. et al. Modelling the effects of cross-sectoral water allocation schemes in Europe. Clim. Change 128, 229–244 (2015).

    Article  Google Scholar 

  21. 21.

    Eisner, S. et al. An ensemble analysis of climate change impacts on streamflow seasonality across 11 large river basins. Clim. Change 141, 401–417 (2017).

    Article  Google Scholar 

  22. 22.

    aus der Beek, T. et al. Modelling historical and current irrigation water demand on the continental scale: Europe. Adv. Geosci. 27, 79–85 (2010).

    Article  Google Scholar 

  23. 23.

    Richter, B. D., Davis, M. M., Apse, C. & Konrad, C. A presumptive standard for environmental flow protection. River Res. Appl. 28, 1312–1321 (2012).

    Article  Google Scholar 

  24. 24.

    Hoekstra, A. Y. et al. Global monthly water scarcity: blue water footprints versus blue water availability. PLoS ONE 7, e32688 (2012).

    CAS  Article  Google Scholar 

  25. 25.

    Gleeson, T., Wada, Y., Bierkens, M. & van Beek, L. Water balance of global aquifers revealed by groundwater footprint. Nature 488, 197–200 (2012).

    CAS  Article  Google Scholar 

  26. 26.

    BGR/UNESCO. Groundwater Resources of the World 1:25,000,000 (BGR, 2008); https://www.whymap.org

  27. 27.

    Gleick, P. H. Global freshwater resources: soft-path solutions for the 21st century. Science 302, 1524–1528 (2003).

    CAS  Article  Google Scholar 

  28. 28.

    Molden, D. et al. Improving agricultural water productivity: between optimism and caution. Agric. Water Manage. 97, 528–535 (2010).

    Article  Google Scholar 

  29. 29.

    Zhao, X. et al. Burden shifting of water quantity and quality stress from megacity Shanghai. Water Resour. Res. 52, 6916–6927 (2016).

    Article  Google Scholar 

  30. 30.

    Cosgrove, W. J. & Loucks, D. P. Water management: current and future challenges and research directions. Water Resour. Res. 51, 4823–4839 (2015).

    Article  Google Scholar 

  31. 31.

    Kiparsky, M., Sedlack, D. L., Thompson, B. H. Jr. & Truffer, B. The innovation deficit in urban water: the need for an integrated perspective on institutions, organizations, and technology. Environ. Eng. Sci. 30, 395–408 (2013).

    CAS  Article  Google Scholar 

  32. 32.

    Schneider, C., Flörke, M., Eisner, S. & Voss, F. Large scale modelling of bankfull flow: an example for Europe. J. Hydrol. 408, 235–245 (2011).

    Article  Google Scholar 

  33. 33.

    Verzano, K. et al. Modeling variable river flow velocity on continental scale: current situation and climate change impacts in Europe. J. Hydrol. 424–425, 238–251 (2012).

    Article  Google Scholar 

  34. 34.

    Lehner, B., Verdin, K. & Jarvis, A. New global hydrography derived from spaceborne elevation data. Eos. Trans. 89, 93–94 (2008).

    Article  Google Scholar 

  35. 35.

    Schneider, C., Flörke, M., De Stefano, L. & Petersen-Perlman, J. D. Hydrological threats for riparian wetlands of international importance — a global quantitative and qualitative analysis. Hydrol. Earth Syst. Sci. 21, 2799–2815 (2017).

    Article  Google Scholar 

  36. 36.

    Eisner, S. Comprehensive Evaluation of the WaterGAP3 Model across Climatic, Physiographic, and Anthropogenic Gradients. PhD thesis, Univ. Kassel (2016).

  37. 37.

    Döll, P. et al. Impact of water withdrawals from groundwater and surface water on continental water storage variations. J. Geodyn. 59–60, 143–156 (2012).

    Article  Google Scholar 

  38. 38.

    Shiklomanov, I. in World Water Scenarios: Analyzing Global Water Resources and Use (ed. Rijsberman, F. R.) Ch. 12, 160–203 (Earthscan Publications, London, 2000).

  39. 39.

    Utility Data Institute. World Electric Power Plants Data Base (Platts Energy InfoStore, 2004); https://infostore.platts.com/infostore/samples/descmeth.pdf

  40. 40.

    Flörke, M., Bärlund, I. & Kynast, E. Will climate change affect the electricity production sector? A European study. J. Water Clim. Change 3, 44–54 (2012).

    Article  Google Scholar 

  41. 41.

    Siebert, S., Henrich, V., Frenken, K. & Burke, J. Update of the Global Map of Irrigation Areas to Version 5 (University of Bonn, Bonn; FAO, Rome; 2013).

  42. 42.

    Siebert, S. et al. A global data set of the extent of irrigated land from 1900 to 2005. Hydrol. Earth Syst. Sci. 19, 1521–1545 (2015).

    Article  Google Scholar 

  43. 43.

    Rohwer, J., Gerten, D. & Lucht, W. Development of Functional Types of Irrigation for Improved Global Crop Modelling Report 104 (Potsdam Institute for Climate Impact Research, Potsdam, 2007).

    Google Scholar 

  44. 44.

    Rost, S. et al. Agricultural green and blue water consumption and its influence on the global water system. Water Resour. Res. 44, W09405 (2008).

    Article  Google Scholar 

  45. 45.

    Alcamo, J. et al. Development and testing of the WaterGAP 2 global model of water use and availability. Hydrolog. Sci. J. 48, 317–337 (2003).

    Article  Google Scholar 

  46. 46.

    FAOSTAT. Live Animals and Livestock Primary, 2014. http://faostat.fao.org/site/339/default.aspx (FAO, 2014).

  47. 47.

    McDonald, R. I., Weber, K. F., Padowski, J., Boucher, T. & Shemie, D. Estimating watershed degradation over the last century and its impact on water-treatment costs for the world’s large cities. Proc. Natl Acad. Sci. USA 113, 9117–9122 (2016).

    CAS  Article  Google Scholar 

  48. 48.

    Balk, D. in Global Mapping of Human Settlement: Experiences, Data Sets, and Prospects (eds. Gamba, P. & Herold, M.) 145–161 (Taylor and Francis, New York, 2009).

  49. 49.

    CIESIN, Columbia University, IFPRI, World Bank, CIAT. Global Rural–Urban Mapping Project (GRUMP): Urban Extents (Center for International Earth Science Information Network, 2004); http://sedac.ciesin.columbia.edu/data/collection/grump-v1

  50. 50.

    O’Neill, B. C. et al. A new scenario framework for climate change research: the concept of shared socioeconomic pathways. Clim. Change 122, 387–400 (2014).

    Article  Google Scholar 

  51. 51.

    van Vuuren, D. P. et al. The representative concentration pathways: an overview. Clim. Change 109, 5–31 (2011).

    Article  Google Scholar 

  52. 52.

    Piani, C. et al. Statistical bias correction of global simulated daily precipitation and temperature for the application of hydrological models. J. Hydrol. 395, 199–215 (2010).

    Article  Google Scholar 

  53. 53.

    Hempel, S., Frieler, K., Warszawski, L., Schewe, J. & Piontek, F. A. Trend-preserving bias correction — the ISI-MIP approach. Earth Syst. Dyn. 4, 219–236 (2013).

    Article  Google Scholar 

  54. 54.

    Warszawski, L. et al. The inter-sectoral impact model intercomparison project (ISI-MIP): project framework. Proc. Natl Acad. Sci. USA 111, 3228–3232 (2014).

    CAS  Article  Google Scholar 

  55. 55.

    Masui, T. et al. An emission pathway for stabilization at 6 Wm−2 radiative forcing. Clim. Change 109, 59–76 (2011).

    CAS  Article  Google Scholar 

  56. 56.

    Wada, Y. et al. Multimodel projections and uncertainties of irrigation water demand under climate change. Geophys. Res. Lett. 40, 4626–4632 (2013).

    Article  Google Scholar 

  57. 57.

    Brauman, K. A., Richter, B. D., Postel, S., Malsy, M. & Flörke, M. Water depletion: an improved metric for incorporating seasonal and dry-year water scarcity into water risk assessments. Elem. Sci. Anth. 4, 83 (2016).

    Article  Google Scholar 

  58. 58.

    Poff, N. L. et al. The natural flow regime. Bioscience 47, 769–784 (1997).

    Article  Google Scholar 

  59. 59.

    Poff, N. L. & Zimmerman, J. K. H. Ecological responses to altered flow regimes: a literature review to inform the science and management of environmental flows. Freshw. Biol. 55, 194–205 (2010).

    Article  Google Scholar 

  60. 60.

    Acreman, M. C. et al. The changing role of ecohydrological science in guiding environmental flows. Hydrol. Sci. J. 59, 433–450 (2014).

    Article  Google Scholar 

  61. 61.

    Müller Schmied, H. et al. Sensitivity of simulated global-scale freshwater fluxes and storages to input data, hydrological model structure, human water use and calibration. Hydrol. Earth Syst. Sci. 18, 3511–3538 (2014).

    Article  Google Scholar 

  62. 62.

    Portmann, F. T., Döll, P., Eisner, S. & Flörke, M. Impact of climate change on renewable groundwater resources: assessing the benefits of avoided greenhouse gas emissions using selected CMIP5 climate projections. Environ. Res. Lett. 8, 024023 (2013).

    Article  Google Scholar 

Download references

Author information

Affiliations

Authors

Contributions

M.F. and R.I.M. designed the study, M.F. drafted the manuscript and performed the analyses. R.I.M. provided all information on basin transfers, C.S. implemented basin transfers into the model and prepared global gridded data of water availability and sectoral water uses. All authors discussed the results and contributed to the manuscript.

Corresponding author

Correspondence to Martina Flörke.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Tables 1–6.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Flörke, M., Schneider, C. & McDonald, R.I. Water competition between cities and agriculture driven by climate change and urban growth. Nat Sustain 1, 51–58 (2018). https://doi.org/10.1038/s41893-017-0006-8

Download citation

Further reading