Abstract:
Study Region: The Kabompo River Basin (KRB) in Zambia is one of the 13 basins found in the
Zambezi River Basin in Southern African region.
Study Focus: Global Climate Model (GCMs) projections have spatial resolution of up to several
hundred kilometres, which may not be adequate for capturing local details mostly needed for
impact assessment at local and regional scale. Downscaling techniques developed to improve the
detail include; regional climate modelling and statistical techniques linking climate information
at GCM resolution with that at local scale. This paper deals with evaluation and assessment of the
impact of climate change on water balance for the KRB. In order to evaluate climate change
impact, six bias–corrected and downscaled GCM outputs were acquired and used as inputs for
hydrological modelling with the SWAT model to determine the impact under two future climate
scenarios.
New Hydrological Insights for the Region: The results indicate that the future catchment water
balance for KRB under RCP4.5 will have insignificant variation from the current catchment water
balance as annual statistics show that rainfall will reduce by 1 % while water yield and runoff
will increase by 5 % and 6 % respectively. Meanwhile under RCP8.5, annual statistics show that
rainfall will increase by 19 % while water yield and runoff will increase by 40 % and 65 %
respectively and resulting in a significant increase in catchment water balance.
