Simulation of the Rainfall Regime over Ghana from CORDEX

Kwadwo Owusu, Nana Ama Browne Klutse

Department of Geography and Resource Development, University of Ghana, Accra, Ghana.
Ghana Space Science and Technology Center, Ghana Atomic Energy Commission, Accra, Ghana.

DOI: 10.4236/ijg.2013.44072                

Abstract

This paper investigates how well the rainfall regime on which many livelihoods depend, in Ghanais well represented by the Coordinated Regional Climate Downscaling Experiment (CORDEX). The objective of the study is to demonstrate how well the ten CORDEX models are able to capture the spatial and temporal rainfall seasonality over the southern and northern sub-sections ofGhana. The choice of the sub-sections is based on the fact that south of 8°N experiences a bi-modal rainfall regime while the north has a uni-modal regime. The results indicate that the rainfall overGhanais associated with high levels of variability at the inter-annual time scale. Particularly over the southern part ofGhana, all the models follow the same trend as represented overGhanawith similar rainfall values as the observation. Over the northern part ofGhana, models record relatively low rainfall agreeing with the observation. However, most of the models overestimate the northern region rainfall as it is in the case of the southern Ghana. CORDEX as shown in this analysis could be useful in providing Ghana with at least 10 different model outputs for impact analysis. Caution is however given that, since individual models give different performance and the fact that models in general have their inherent deficiencies, an ensemble mean of the models could provide a better result.

Keywords

CORDEX; Rainfall Modelling; Climate Change; Climate Variability; Climate Prediction; Ghana

Conflicts of Interest

The authors declare no conflicts of interest.

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