Original citation: Dieppois, B. , Pohl, B. , Rouault, M. , New, M. , Lawler, D. and Keenlyside, N. (2016) Interannual to Interdecadal variability of winter and summer southern African rainfall, and their teleconnections. Abstract This study examines for the first time the changing characteristics of summer and winter southern African rainfall and their teleconnections with large-scale climate through the dominant time scales of variability. As determined by wavelet analysis, the austral summer and winter rainfall indices exhibit three significant time scales of variability over the twentieth century: interdecadal (15-28 years), quasi-decadal (8-13 years), and interannual (2-8 years). Teleconnections with global sea surface temperature and atmospheric circulation anomalies are established here but are different for each time scale. Tropical/subtropical teleconnections emerge as the main driver of austral summer rainfall variability. Thus, shifts in the Walker circulation are linked to the El Niño-Southern Oscillation (ENSO) and, at decadal time scales, to decadal ENSO-like patterns related to the Pacific Decadal Oscillation and the Interdecadal Pacific Oscillation. These global changes in the upper zonal circulation interact with asymmetric ocean-atmospheric conditions between the South Atlantic and South Indian Oceans; together, these lead to a shift in the South Indian Convergence Zone and a modulation of the development of convective rain-bearing systems over southern Africa in summer. Such regional changes, embedded in quasi-annular geopotential patterns, consist of easterly moisture fluxes from the South Indian High, which dominate southerly moisture fluxes from the South Atlantic High. Austral winter rainfall variability is more influenced by midlatitude atmospheric variability, in particular the Southern Annular Mode. The rainfall changes in the southwestern regions of southern Africa are determined by asymmetrical changes in the midlatitude westerlies between the Atlantic and Indian Oceans.

Original citation: Dieppois, B. , Rouault, M. and New, M. (2015) The impact of ENSO on Southern African rainfall in CMIP5 ocean atmosphere coupled climate models. Climate Dynamics, volume 45 (9): 2425-2442. DOI 10.1007/s00382-015-2480-x http://dx.doi.org/10.1007/s00382-015-2480-x Springer Berlin HeidelbergThe final publication is available at Springer via http://dx.doi.org/10.1007/s00382-015-2480-x Copyright © and Moral Rights are retained by the author(s) and/ or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This item cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders. which can lead to the wrong sign in rainfall anomalies in the northwest part of South Africa. CURVE is the Institutional Repository for Coventry University

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