Assessment of future variability in extreme precipitation and the potential effects on the wadi flow regime

  • Luminda Niroshana Gunawardhana
  • Ghazi A. Al-Rawas
  • So Kazama
  • Khalid A. Al-Najar


The objective of this study is to investigate how the magnitude and occurrence of extreme precipitation events are affected by climate change and to predict the subsequent impacts on the wadi flow regime in the Al-Khod catchment area, Muscat, Oman. The tank model, a lumped-parameter rainfall-runoff model, was used to simulate the wadi flow. Precipitation extremes and their potential future changes were predicted using six-member ensembles of general circulation models (GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Yearly maxima of the daily precipitation and wadi flow for varying return periods were compared for observed and projected data by fitting the generalized extreme value (GEV) distribution function. Flow duration curves (FDC) were developed and compared for the observed and projected wadi flows. The results indicate that extreme precipitation events consistently increase by the middle of the twenty-first century for all return periods (49–52 %), but changes may become more profound by the end of the twenty-first century (81–101 %). Consequently, the relative change in extreme wadi flow is greater than twofolds for all of the return periods in the late twenty-first century compared to the relative changes that occur in the mid-century period. Precipitation analysis further suggests that greater than 50 % of the precipitation may be associated with extreme events in the future. The FDC analysis reveals that changes in low-to-moderate flows (Q60–Q90) may not be statistically significant, whereas increases in high flows (Q5) are statistically robust (20 and 25 % for the mid- and late-century periods, respectively).


Climate change Weather generator Frequency analysis Oman 


  1. Agarwal, A., Babel, M. S., & Maskey, S. (2014). Analysis of future precipitation in the Koshi river basin, Nepal. Journal of Hydrology, 513, 422–434.CrossRefGoogle Scholar
  2. Al Barwani, A., & Helmi, T. (2006). Sea water intrusion in coastal aquifer. A case study for the area between Seeb and Suwaiq (1984–2005). Agriculture and Marine Science, 11, 55–69.Google Scholar
  3. Alexander, L. V., Zhang, X., Peterson, T. C., Caesar, J., Gleason, B., Tank, A. M. G. K., et al (2006). Global observed changes in daily climate extremes of temperature and precipitation. Journal of Geophysical Research, D05109. doi: 10.1029/2005JD006290.
  4. Allen, M. R., & Ingram, W. J. (2002). Constraints on future changes in climate and the hydrological cycle. Nature, 419, 224–232.CrossRefGoogle Scholar
  5. Al-Rawas, A. G., & Valeo, C. (2009). Characteristics of rainstorm temporal distributions in arid mountainous and coastal regions. Journal of Hydrology, 376, 318–326.CrossRefGoogle Scholar
  6. Al-Rawas, A. G., & Valeo, C. (2010). Relationship between wadi drainage characteristics and peak-flood flows in arid northern Oman. Hydrological Sciences Journal, 55, 377–393.CrossRefGoogle Scholar
  7. Cooper, V. A., Nguyen, V. T. V., & Nicell, J. A. (2007). Calibration of conceptual rainfall-runoff models using global optimization methods with hydrologic process-based parameter constraints. Journal of Hydrology, 334, 455–466.CrossRefGoogle Scholar
  8. Cubash, U. and Meehl, G. A. (2001). Projections of future climate change. Climate change 2001: the scientific basis. Contribution of Working Group 1 to the Third IPCC Scientific Assessment, J. T. Houghton et al., Eds., Cambridge University Press: 524–582.Google Scholar
  9. Demaria, E. M. C., Maurer, E. P., Thrasher, B., Vicuna, S., & Meza, F. J. (2013). Climate change impacts on an alpine watershe\d in Chile: do new model projections change the story? Journal of Hydrology, 502, 128–138.CrossRefGoogle Scholar
  10. Groisman, P. Y., Knight, R. W., Easterling, D. R., Karl, T. R., Hegerl, T. C., & Razuvaev, V. N. (2005). Trends in intense precipitation in the climate record. Journal of Climate, 18, 1326–1350.CrossRefGoogle Scholar
  11. Gunasekara, N. K., Kazama, S., Yamazaki, D., & Oki, T. (2013). The effects of country-level population policy for enhancing adaptation to climate change. Hydrology and Earth System Sciences, 17, 4429–4440.CrossRefGoogle Scholar
  12. Gunawardhana, L. N., & Al-Rawas, A. G. (2014). Trends in extreme temperature and precipitation in Muscat, Oman. IAHS-AISH Proceedings and Reports, 364, 57–63.CrossRefGoogle Scholar
  13. Gunawardhana, L. N., & Kazama, S. (2012). A water availability and low-flow analysis of the Tagliamento River discharge in Italy under changing climate conditions. Hydrology and Earth System Sciences, 16, 1033–1045.CrossRefGoogle Scholar
  14. Jenkinson, A. F. (1955). The frequency distribution of the annual maximum (or minimum) values of meteorological elements. Quarterly Journal of the Royal Meteorological Society, 81, 158–171.CrossRefGoogle Scholar
  15. Karl, T. R., & Trenberth, K. E. (2003). Modern global climate change. Science, 302, 1719–1723.CrossRefGoogle Scholar
  16. Kharin, V. V., Zwiers, F. W., Zhang, X., & Hegerl, G. C. (2007). Changes in temperature and precipitation extremes in the IPCC ensemble of global coupled model simulations. Journal of Climate, 20, 1419–1444.CrossRefGoogle Scholar
  17. Kharin, V. V., Zwiers, F. W., Zhang, X., & Wehner, M. (2013). Changes in temperature and precipitation extremes in the CMIP5 ensemble. Climatic Change, 119, 345–357.CrossRefGoogle Scholar
  18. Maeda, M., & Bergstrom, L. F. (2000). Leaching patterns of heavy metals and nitrogen evaluated with a modified tanks-in-series model. Journal of Contaminant Hydrology, 43, 165–185.CrossRefGoogle Scholar
  19. Moriasi, D. N., Arnold, J. G., Liew, M. W., Bingner, R. L., Harmel, R. D., & Veith, T. (2007). Model evaluation guidelines for systematic quantification of accuracy in watershed simulations. Transaction of the American Society of Agricultural Engineers, 50, 885–900.Google Scholar
  20. Moss, R. H., Edmonds, J. A., Hibbard, K. A., Manning, M. R., Rose, S. K., Vuuren, D. P., et al (2010). The next generation of scenarios for climate change research and assessment. Nature, 463, 747–756.CrossRefGoogle Scholar
  21. Semenov, M. A. and Barrow, E. M. (2002). LARS-WG: A stochastic weather generator for use in climate impact studies, Version 3.0, User’s manual.Google Scholar
  22. Semenov, M. A., & Stratonovitch, P. (2010). The use of multi-model ensembles from global climate models for impact assessments of climate change. Climate Research, 41, 1–14.CrossRefGoogle Scholar
  23. Smakhtin, V. U. (2001). Low flow hydrology: a review. Journal of Hydrology, 240, 147–186.CrossRefGoogle Scholar
  24. Stahli, M., Badoux, A., Ludwig, A., Steiner, K., Zappa, M., & Hegg, C. (2011). One century of hydrological monitoring in two small catchments with different forest coverage. Environmental Monitoring and Assessment, 174, 91–106.CrossRefGoogle Scholar
  25. Sugawara, M. (1995). Tank model, computer models of watershed hydrology, in: Water resources publications, edited by: Singh. Highlands Ranch, CO, USA: V. J.Google Scholar
  26. Symon, C. (2013). Climate change: actions, trends and implications for business. In The IPCC fifth assessment report (pp. 524–582). Cambridge University Press: Working Group 1.Google Scholar
  27. Trenberth, K. E., Dai, A., Rasmussen, R. M., & Parsons, D. B. Z. (2003). The changing character of precipitation. Bulletin of the American Meteorological Society, 84, 1205–1217.CrossRefGoogle Scholar
  28. Tureyen, O. I., & Akyap, E. (2011). A generalized non-isothermal tank model for liquid dominated geothermal reservoirs. Geothermics, 40, 50–57.CrossRefGoogle Scholar
  29. Westra, S., Alexander, L. V., & Zwiers, F. W. (2013). Global increasing trends in annual maximum daily precipitation. Journal of Climate, 26, 3904–3918.CrossRefGoogle Scholar
  30. Yokoo, Y., Kazama, S., Sawamoto, M., & Nishimura, H. (2001). Regionalization of lumped water balance model parameters based on multiple regression. Journal of Hydrology, 246, 209–222.CrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Luminda Niroshana Gunawardhana
    • 1
  • Ghazi A. Al-Rawas
    • 1
  • So Kazama
    • 2
  • Khalid A. Al-Najar
    • 3
  1. 1.Civil and Architectural Engineering Department, College of EngineeringSultan Qaboos UniversityMuscatSultanate of Oman
  2. 2.Graduate School of Environmental StudiesTohoku UniversitySendaiJapan
  3. 3.Civil Aviation and Meteorology, Meteorology DepartmentSalalah AirportSalalahOman

Personalised recommendations