International Research Journal of Innovations in Engineering and Technology - IRJIET International Open Access, Monthly, Peer Reviewed, Reputed Journal ISSN (online): 2581-3048

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DOI Prefix: 10.47001/IRJIET

Comparing the Performance of Six Regional Climate Models and Their Ensemble over West Africa

Abstract

This study assessed the ability of six CORDEX Regional Climate Models (RCMs) in comparison to their ensemble mean (ENSEMBLE) in reproducing rainfall distribution over West Africa from 1951 to 2005. Using annual and seasonal climatological and statistical description, all the RCMs and their ensemble were evaluated against Climate Research Unit (CRU) rainfall observational product.  over three homogenous climatic zones of Guinea Coast, Savannah and Sahel. Results from annual rainfall evaluation indicated that most of the RCMs and ENSEMBLE captured the temporal and spatial distribution over West Africa as they simulates single rainfall peak over the Savannah and Sahel zones. Annual statistical evaluation performed shows that most of the RCMs and ENSEMBLE are in good agreement with the CRU. In particular, RACMO outperformed the ENSEMBLE in the Guinea Coast just as CRCM, HIRHAM, RCA and REMO did over the Savannah. Seasonally, the statistical performance of the six RCMs and the ENSEMBLE in DJF season is relatively poor while most of the individual RCMs performed better than ENSEMBLE in SON season over entire West Africa, Savannah and Sahelian zone. Spatial pattern also revealed that most of the RCMs replicated mean seasonal distribution in DJF and MAM season. The overall performance of all the RCMs and the ENSEMBLE varies in different climatic zones and from one season to the other. However, CRCM and RCA consistently performed better than others and can be used in place of the ENSEMBLE to study rainfall over West Africa.

Country : Nigeria

1 Vincent O. Ajayi

  1. Department of Meteorology and Climate Science, Federal University of Technology, Akure, PMB 704 Akure, Ondo State, Nigeria

IRJIET, Volume 6, Issue 6, June 2022 pp. 68-84

doi.org/10.47001/IRJIET/2022.606010

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