Articles | Volume 15, issue 3
Hydrol. Earth Syst. Sci., 15, 931–941, 2011

Special issue: Uncertainty in climate change impacts on basin-scale freshwater...

Hydrol. Earth Syst. Sci., 15, 931–941, 2011

Research article 16 Mar 2011

Research article | 16 Mar 2011

Uncertainty in water resources availability in the Okavango River basin as a result of climate change

D. A. Hughes1, D. G. Kingston2, and M. C. Todd3 D. A. Hughes et al.
  • 1Institute for Water Research, Rhodes University, Grahamstown, South Africa
  • 2Department of Geography, University of Otago, P.O. Box 56, Dunedin, New Zealand
  • 3Department of Geography, University of Sussex, Brighton, UK

Abstract. This paper assesses the hydrological response to scenarios of climate change in the Okavango River catchment in Southern Africa. Climate scenarios are constructed representing different changes in global mean temperature from an ensemble of 7 climate models assessed in the IPCC AR4. The results show a substantial change in mean flow associated with a global warming of 2 °C. However, there is considerable uncertainty in the sign and magnitude of the projected changes between different climate models, implying that the ensemble mean is not an appropriate generalised indicator of impact. The uncertainty in response between different climate model patterns is considerably greater than the range due to uncertainty in hydrological model parameterisation. There is also a clear need to evaluate the physical mechanisms associated with the model projected changes in this region. The implications for water resource management policy are considered.