Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Rainfall consistently enhanced around the Gezira Scheme in East Africa due to irrigation

Nature Geoscience volume 8, pages 763–767 (2015)Cite this article

Subjects

Abstract

Land-use and land-cover changes have significantly modified regional climate patterns around the world1,2. In particular, the rapid development of large-scale cropland irrigation over the past century has been investigated in relation to possible modification of regional rainfall3,4,5,6,7,8,9,10,11,12,13,14. In regional climate simulations of the West African Sahel, hypothetical large-scale irrigation schemes inhibit rainfall over irrigated areas but enhance rainfall remotely13,14. However, the simulated influence of large-scale irrigation schemes on precipitation patterns cannot be substantiated without direct comparison to observations15. Here we present two complementary analyses: numerical simulations using a regional climate model over an actual, large-scale irrigation scheme in the East African Sahel—the Gezira Scheme—and observational analyses over the same area. The simulations suggest that irrigation inhibits rainfall over the Gezira Scheme and enhances rainfall to the east. Observational analyses of rainfall, temperature and streamflow in the same region support the simulated results. The findings are consistent with a mechanistic framework in which irrigation decreases surface air temperature, causing atmospheric subsidence over the irrigated area and clockwise wind anomalies (in background southwesterly winds) that increase upward vertical motion to the east. We conclude that irrigation development can consistently modify rainfall patterns in and around irrigated areas, warranting further examination of potential agricultural, hydrologic and economic implications.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Background information regarding irrigation in the Gezira Scheme.
Figure 2: Comparison of simulated and observed changes in rainfall.
Figure 3: Temporal and spatial changes in rainfall from station observations.
Figure 4: Spatial changes in horizontal wind and temporal changes in surface air temperature.

Similar content being viewed by others

References

  1. Pielke, R. A. Sr et al. Land use/land cover changes and climate: Modeling analysis and observational evidence. WIREs Clim. Change 2, 828–850 (2011).

    Article  Google Scholar 

  2. Mahmood, R. et al. Land cover changes and their biogeophysical effects on climate. Int. J. Climatol. 34, 929–953 (2014).

    Article  Google Scholar 

  3. Stidd, C. K. Irrigation increases rainfall? Science 188, 279–281 (1975).

    Article  Google Scholar 

  4. Barnston, A. G. & Schickedanz, P. T. The effect of irrigation on warm season precipitation in the Southern Great Plains. J. Clim. Appl. Meteorol. 23, 865–888 (1984).

    Article  Google Scholar 

  5. Douglas, E. M., Beltrán-Przekurat, A., Niyogi, D., Pielke, R. A. Sr & Vörösmarty, C. J. The impact of agricultural intensification and irrigation on land–atmosphere interactions and Indian monsoon precipitation—A mesoscale modeling perspective. Glob. Planet. Change 67, 117–128 (2009).

    Article  Google Scholar 

  6. DeAngelis, A. et al. Evidence of enhanced precipitation due to irrigation over the Great Plains of the United States. J. Geophys. Res. 115, D15115 (2010).

    Article  Google Scholar 

  7. Puma, M. J. & Cook, B. I. Effects of irrigation on global climate during the 20th century. J. Geophys. Res. 115, D16120 (2010).

    Article  Google Scholar 

  8. Harding, K. J. & Snyder, P. K. Modeling the atmospheric response to irrigation in the Great Plains. Part I: General impacts on precipitation and the energy budget. J. Hydrometeorol. 13, 1667–1686 (2012).

    Article  Google Scholar 

  9. Qian, Y., Huang, M., Yang, B. & Berg, L. K. A modeling study of irrigation effects on surface fluxes and land–air–cloud interactions in the Southern Great Plains. J. Hydrometeorol. 14, 700–721 (2013).

    Article  Google Scholar 

  10. Lo, M. & Famiglietti, J. S. Irrigation in California’s Central Valley strengthens the southwestern U. S. water cycle. Geophys. Res. Lett. 40, 301–306 (2013).

    Article  Google Scholar 

  11. Wei, J., Dirmeyer, P. A., Wisser, D., Bosilovich, M. G. & Mocko, D. M. Where does the irrigation water go? An estimate of the contribution of irrigation to precipitation using MERRA. J. Hydrometeorol. 14, 275–289 (2013).

    Article  Google Scholar 

  12. Huber, D., Mechem, D. & Brunsell, N. The effects of Great Plains irrigation on the surface energy balance, regional circulation, and precipitation. Climate 2, 103–128 (2014).

    Article  Google Scholar 

  13. Im, E.-S. & Eltahir, E. A. B. Enhancement of rainfall and runoff upstream from irrigation location in a climate model of West Africa. Wat. Resour. Res. 50, 8651–8674 (2014).

    Article  Google Scholar 

  14. Im, E.-S., Marcella, M. P. & Eltahir, E. A. B. Impact of potential large-scale irrigation on the West African monsoon and its dependence on location of irrigated area. J. Clim. 27, 994–1009 (2014).

    Article  Google Scholar 

  15. Xue, Y. Biosphere feedback on regional climate in tropical north Africa. Q. J. R. Meteorol. Soc. B 123, 1483–1515 (1997).

    Article  Google Scholar 

  16. Eltahir, E. A. B. A soil moisture-rainfall feedback mechanism: 1. Theory and observations. Wat. Resour. Res. 34, 765–776 (1998).

    Article  Google Scholar 

  17. Pielke, R. A. Sr Influence of the spatial distribution of vegetation and soils on the prediction of cumulus convective rainfall. Rev. Geophys. 39, 151–177 (2001).

    Article  Google Scholar 

  18. Kueppers, L. M., Snyder, M. A. & Sloan, L. C. Irrigation cooling effect: Regional climate forcing by land-use change. Geophys. Res. Lett. 34, L03703 (2007).

    Article  Google Scholar 

  19. Lee, E., Sacks, W. J., Chase, T. N. & Foley, J. A. Simulated impacts of irrigation on the atmospheric circulation over Asia. J. Geophys. Res. 116, D08114 (2011).

    Google Scholar 

  20. Ozdogan, M., Rodell, M., Beaudoing, H. K. & Toll, D. L. Simulating the effects of irrigation over the United States in a land surface model based on satellite-derived agricultural data. J. Hydrometeorol. 11, 171–184 (2010).

    Article  Google Scholar 

  21. Mahmood, R., Hubbard, K. G., Leeper, R. D. & Foster, S. A. Increase in near-surface atmospheric moisture content due to land use changes: Evidence from the observed dewpoint temperature data. Mon. Weath. Rev. 136, 1554–1561 (2008).

    Article  Google Scholar 

  22. You, L. et al. What is the Irrigation Potential for Africa? A Combined Biophysical and Socioeconomic Approach Discussion Paper 00993 (International Food Policy Research Institute, 2010).

    Google Scholar 

  23. World Development Indicators (WDI) Section 4: Economy (The World Bank, 2010); http://data.worldbank.org/data-catalog/world-development-indicators/wdi-2010

  24. Im, E.-S., Gianotti, R. L. & Eltahir, E. A. B. Improving simulation of the West African monsoon using the MIT Regional Climate Model. J. Clim. 27, 2209–2229 (2014).

    Article  Google Scholar 

  25. Plusquellec, H. The Gezira Irrigation Scheme in Sudan: Objectives, Design, and Performance (The World Bank, 1990); http://documents.worldbank.org/curated/en/1990/05/439697/gezira-irrigation-scheme-sudan-objectives-design-performance

    Google Scholar 

  26. NASA Land Processes Distributed Active Archive Center (LP DAAC), MODIS Aqua MOD 11 (USGS/Earth Resources Observation and Science (EROS) Center, 2014).

    Google Scholar 

  27. Willmott, C. J. & Matsuura, K. Terrestrial Precipitation: Gridded Monthly Time Series (1900–2010) v.3.01 (Center for Climatic Research, Univ. Delaware, 15 October 2014); http://climate.geog.udel.edu/ climate/html_pages/Global2011/README.GlobalTsP2011.html

    Google Scholar 

  28. Peterson, T. C. & Vose, R. S. An overview of the Global Historical Climatology Network temperature database. Bull. Am. Meteorol. Soc. 78, 2837–2849 (1997).

    Article  Google Scholar 

  29. Kalnay, E. et al. The NCEP/NCAR 40-year reanalysis project. Bull. Am. Meteorol. Soc. 77, 437–470 (1996).

    Article  Google Scholar 

  30. Pal, J. S. et al. The ICTP RegCM3 and RegCNET: Regional climate modeling for the developing world. Bull. Am. Meteorol. Soc. 88, 1395–1409 (2007).

    Article  Google Scholar 

  31. Winter, J. M., Pal, J. S. & Eltahir, E. A. B. Coupling of Integrated Biosphere Simulator to Regional Climate Model Version 3. J. Clim. 22, 2743–2756 (2009).

    Article  Google Scholar 

  32. Marcella, M. P. Biosphere—Atmosphere Interactions Over Semi-arid Regions: Modeling the Role of Mineral Aerosols and Irrigation in the Regional Climate System PhD dissertation, Massachusetts Institute of Technology (2012).

  33. Gianotti, R. L. & Eltahir, E. A. B. Regional climate modeling over the Maritime Continent. Part I: New parameterization for convective cloud fraction. J. Clim. 27, 1488–1503 (2014).

    Article  Google Scholar 

  34. Gianotti, R. L. & Eltahir, E. A. B. Regional climate modeling over the Maritime Continent. Part II: New parameterization for autoconversion of convective rainfall. J. Clim. 27, 1504–1523 (2014).

    Article  Google Scholar 

  35. Gianotti, R. L. Convective Cloud and Rainfall Processes over the Maritime Continent: Simulation and Analysis of the Diurnal Cycle PhD dissertation, Massachusetts Institute of Technology (2012).

  36. Sorooshian, S., Li, J., Hus, K. & Gao, X. How significant is the impact of irrigation on the local hydroclimate in California’s Central Valley? Comparison of model results with ground and remote-sensing data. J. Geophys. Res. 116, D06102 (2011).

    Google Scholar 

  37. Sorooshian, S., Li, J., Hus, K. & Gao, X. Influence of irrigation schemes used in regional climate models on evapotranspiration estimation: Results and comparative studies from California’s Central Valley agricultural regions. J. Geophys. Res. 117, D06107 (2012).

    Article  Google Scholar 

  38. Harding, K. J. & Snyder, P. K. Modeling the atmospheric response to irrigation in the Great Plains. Part II: The precipitation of irrigated water and changes in precipitation recycling. J. Hydrometeorol. 13, 1687–1703 (2012).

    Article  Google Scholar 

  39. Marcella, M. & Eltahir, E. A. B. Introducing an irrigation scheme to a regional climate model: A case study over West Africa. J. Clim. 27, 5708–5723 (2014).

    Article  Google Scholar 

  40. Uppala, S., Dee, D., Kobayashi, S., Berrisford, P. & Simmons, A. Towards a climate data assimilation system: Status update of ERA Interim. ECMWF Newslett. 115, 12–18 (2008).

    Google Scholar 

  41. Rayner, N. A., Horton, E. B., Parker, D. E., Folland, C. K. & Hackett, R. B. Version 2.2 of the Global Sea Ice and Sea Surface Temperature Data Set, 1903–1994 Clim. Res. Tech. Note CRTN74 (Hadley Centre, 1996).

    Google Scholar 

  42. Reynolds, R., Rayner, N. A., Smith, T. M., Stokes, D. C. & Wang, W. An improved in situ and satellite SST analysis for climate. J. Clim. 15, 1609–1625 (2002).

    Article  Google Scholar 

  43. Hoerling, M. P., Hurrell, J. W., Eischeid, J. & Phillips, A. Detection and attribution of twentieth-century northern and southern African rainfall change. J. Clim. 19, 3989–4008 (2006).

    Article  Google Scholar 

  44. Nicholson, S. E., Dezfuli, A. K. & Klotter, D. A two-century rainfall dataset for the continent of Africa. Bull. Am. Meteorol. Soc. 93, 1219–1231 (2012).

    Article  Google Scholar 

Download references

Acknowledgements

Funding for this research was provided by the Cooperative Agreement between the Masdar Institute of Science and Technology (Masdar Institute) and the Massachusetts Institute of Technology (MIT), and by the Singapore–Massachusetts Institute of Technology Alliance for Research and Technology (SMART). We are grateful to M. Siam and the other members of the Eltahir Research Group for their support and valuable feedback.

Author information

Author notes

  1. Ross E. Alter and Eun-Soon Im: These authors contributed equally to this work.

Authors and Affiliations

  1. Ralph M. Parsons Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA

    Ross E. Alter & Elfatih A. B. Eltahir

  2. Center for Environmental Sensing and Modeling, Singapore—Massachusetts Institute of Technology Alliance for Research and Technology, Singapore 138602, Singapore

    Eun-Soon Im

Authors
  1. Ross E. Alter
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Eun-Soon Im
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Elfatih A. B. Eltahir
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

E.A.B.E. conceived and supervised the study. E.-S.I. performed the numerical modelling experiments and analysis. R.E.A. performed the observational analyses. R.E.A. wrote the paper, with input from E.-S.I. and E.A.B.E. All authors discussed the results and commented on the manuscript.

Corresponding authors

Correspondence to Ross E. Alter or Eun-Soon Im.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 1898 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Alter, R., Im, ES. & Eltahir, E. Rainfall consistently enhanced around the Gezira Scheme in East Africa due to irrigation. Nature Geosci 8, 763–767 (2015). https://doi.org/10.1038/ngeo2514

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ngeo2514

This article is cited by

Search

Advanced search

Quick links

Nature Briefing Anthropocene

Sign up for the Nature Briefing: Anthropocene newsletter — what matters in anthropocene research, free to your inbox weekly.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing: Anthropocene