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Theoretical and Applied Climatology

, Volume 95, Issue 3–4, pp 407–416 | Cite as

Equatorial African climate teleconnections

  • M. R. Jury
  • E. Matari
  • M. Matitu
Original Paper

Abstract

Teleconnections between equatorial African climate and the surrounding circulation are examined using a convective index over the Congo River Basin in March to May (MAM) and July to September (JAS) seasons. Its influence on the wider region is determined through lag correlation and cross-wavelet analysis. During seasons of deeper convection, easterly winds weaken over the tropical Atlantic (anomalous flow toward Africa), whilst upper westerly winds weaken over southern Africa (in JAS). We view this as zonal overturning with ascent over the equatorial African lowlands and Congo River Basin that spreads moisture to the North African Sahel, with influence from the Pacific El Niño. Another facet of our study is the relationship between East African highlands rainfall and the Indian Ocean circulation. We find coupling between the Indian Ocean Rossby wave, a thermocline oscillation and Walker cell over the Indian Ocean that induces shifts in rainfall, particularly in the October to December season.

Keywords

Indian Ocean Zonal Wind Congo Outgoing Long Wave Radiation African Rainfall 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Physics DepartmentUniversity of Puerto RicoMayaguezUSA
  2. 2.Tanzania Meteorological ServicesDar es SalaamTanzania

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