DOI: 10.1007/s00382-012-1314-3
Scopus记录号: 2-s2.0-84869505288
论文题名: Tropical-temperate interactions over southern Africa simulated by a regional climate model
作者: Vigaud N. ; Pohl B. ; Crétat J.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2012
卷: 39, 期: 12 起始页码: 2895
结束页码: 2916
语种: 英语
英文关键词: Regional modeling
; Southern Africa climate
; Tropical-temperate interactions
英文摘要: The Weather Research and Forecasting model (WRF) forced by ERA40 re-analyses, is used to examine, at regional scale, the role of key features of the local atmospheric circulation on the origin and development of Tropical Temperate Troughs (TTTs) representing a major contribution to South African rainfall during austral summer. A cluster analysis applied on 1971-2000 ERA40 and WRF simulated daily outgoing longwave radiation reveals for the November-February season three coherent regimes characteristic of TTTs over the region. Analyses of WRF simulated TTTs suggest that their occurrence is primarily linked with mid-latitude westerly waves and their phasing. Ensemble experiments designed for the case of austral summer 1996/1997 allow to examine the reproducibility of TTT events. The results obtained illustrate the importance of westerly waves phasing regarding the persistence of rain-producing continental TTT events. Moreover, oceanic surface conditions prevailing over the Agulhas current regions of the South West Indian Ocean (SWIO) are also found to influence TTT persistence for regional experiments with an oceanic mixed layer, warmer sea surface temperatures being associated with increased moisture advection from the SWIO where latent heat release is enhanced, favoring baroclinic instability and thus sustaining convection activity locally. © 2012 Springer-Verlag. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/55116
Appears in Collections: 过去全球变化的重建
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作者单位: Centre de Recherches de Climatologie, UMR 6282 Biogéosciences CNRS/Université de Bourgogne, Dijon, France
Recommended Citation:
Vigaud N.,Pohl B.,Crétat J.. Tropical-temperate interactions over southern Africa simulated by a regional climate model[J]. Climate Dynamics,2012-01-01,39(12)