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Article Number - 9AB281565893


Vol.12(15), pp. 142-154 , August 2017
DOI: 10.5897/SRE2017.6525
ISSN: 1992-2248



Full Length Research Paper

West African Monsoon (WAM) and Atlantic Cold Tongue (ACT) onsets using Regional Climate Model



K. Benjamin KOUASSI
  • K. Benjamin KOUASSI
  • Laboratory of Atmospheric Physics and Fluid Mechanics, University F.H.B. of Cocody-Abidjan, 22 BP 582 Abidjan 22, Côte d’Ivoire.
  • Google Scholar
Adama DIAWARA
  • Adama DIAWARA
  • Laboratory of Atmospheric Physics and Fluid Mechanics, University F.H.B. of Cocody-Abidjan, 22 BP 582 Abidjan 22, Côte d’Ivoire.
  • Google Scholar
K. Yves KOUADIO
  • K. Yves KOUADIO
  • Laboratory of Atmospheric Physics and Fluid Mechanics, University F.H.B. of Cocody-Abidjan, 22 BP 582 Abidjan 22, Côte d’Ivoire.
  • Google Scholar
Fidele YOROBA
  • Fidele YOROBA
  • Laboratory of Atmospheric Physics and Fluid Mechanics, University F.H.B. of Cocody-Abidjan, 22 BP 582 Abidjan 22, Côte d’Ivoire.
  • Google Scholar
Elisee TOUALY
  • Elisee TOUALY
  • Laboratory of Atmospheric Physics and Fluid Mechanics, University F.H.B. of Cocody-Abidjan, 22 BP 582 Abidjan 22, Côte d’Ivoire.
  • Google Scholar







 Received: 11 July 2017  Accepted: 15 August 2017  Published: 18 August 2017

Copyright © 2017 Author(s) retain the copyright of this article.
This article is published under the terms of the Creative Commons Attribution License 4.0


This study focused on the occurrences and relationships of the Atlantic Cold Tongue (ACT) and the West African Monsoon (WAM) onsets in the Sudano-Sahelian region during 1983-2000. Two simulations (WAFSSTERA and WAFSSTREY) were used to investigate the sensitivity of the Regional Atmospheric Model (MAR) for two different datasets of sea surface temperature (ERA-40 and Reynolds SST datasets). The MAR reproduced the rainfall high values in the Guinean zone. A band of weak precipitation (<1 mm/day) was observed in the two simulations. WAFSSTERA gave more annual daily average rainfall (~1.6 mm/day) than WAFSSTREY. The simulated onset date index (ODI) of WAM showed more northward penetration of monsoon flow, particularly during flood years in the Gulf of Guinea. These results also indicated that the monsoon onset did not depend on the SST dataset used to force the model. Finally, the negative difference between ODIs and ACT onset date could be due to warm SST. The yearly evolution of the southern heat transport was also in agreement with this difference. It showed yearly succession of negative and positive anomalies around 7.5°N (mean rainy equilibrium position over West Africa). Such study could be useful for the forecast of WAM onset and ACT scenario relationships.

Key words: Atlantic cold tongue, onset date index, regional climate model, sea surface temperature, West African Monsoon.

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APA KOUASSI, K. B., DIAWARA, A., KOUADIO, K. Y., YOROBA, F., & TOUALY, E. (2017). West African Monsoon (WAM) and Atlantic Cold Tongue (ACT) onsets using Regional Climate Model. Scientific Research and Essays, 12(15), 142-154.
Chicago K. Benjamin KOUASSI, Adama DIAWARA, K. Yves KOUADIO, Fidèle YOROBA, and Elis&ee TOUALY. "West African Monsoon (WAM) and Atlantic Cold Tongue (ACT) onsets using Regional Climate Model." Scientific Research and Essays 12, no. 15 (2017): 142-154.
MLA K. Benjamin KOUASSI, et al. "West African Monsoon (WAM) and Atlantic Cold Tongue (ACT) onsets using Regional Climate Model." Scientific Research and Essays 12.15 (2017): 142-154.
   
DOI 10.5897/SRE2017.6525
URL http://www.academicjournals.org/journal/SRE/article-abstract/9AB281565893

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