DOI: 10.1175/JCLI-D-17-0311.1
Scopus记录号: 2-s2.0-85048208473
论文题名: Future precipitation projections over central and Southern Africa and the adjacent Indian Ocean: What causes the changes and the uncertainty?
作者: Lazenby M.J. ; Todd M.C. ; Chadwick R. ; Wang Y.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2018
卷: 31, 期: 12 起始页码: 4807
结束页码: 4826
语种: 英语
英文关键词: Climate change
; Climate models
; Dynamics
; Precipitation
; Thermodynamics
; Tropics
Scopus关键词: Climate models
; Dynamics
; Oceanography
; Precipitation (chemical)
; Rain
; Thermodynamics
; Tropics
; Climate change adaptation
; Convergence zones
; Decomposition methods
; Dynamical components
; Future projections
; Physical mechanism
; South Indian Ocean
; Southern indian ocean
; Climate change
; climate change
; climate modeling
; climate prediction
; CMIP
; precipitation (climatology)
; rainfall
; thermodynamics
; Central Africa
; Indian Ocean
; Southern Africa
英文摘要: Future projections of precipitation at regional scales are vital to inform climate change adaptation activities. Therefore, is it important to quantify projected changes and associated uncertainty, and understand model processes responsible. This paper addresses these challenges for southern Africa and the adjacent Indian Ocean focusing on the local wet season. Precipitation projections for the end of the twenty-first century indicate a pronounced dipole pattern in the CMIP5 multimodel mean. The dipole indicates future wetting (drying) to the north (south) of the climatological axis of maximum rainfall, implying a northward shift of the ITCZ and south Indian Ocean convergence zone that is not consistent with a simple ''wet get wetter'' pattern. This pattern is most pronounced in early austral summer, suggesting a later and shorter wet season over much of southern Africa. Using a decomposition method we determine physical mechanisms underlying this dipole pattern of projected change, and the associated intermodel uncertainty. The projected dipole pattern is largely associated with the dynamical component of change indicative of shifts in the location of convection. Over the Indian Ocean, this apparent northward shift in the ITCZ may reflect the response to changes in the north-south SST gradient over the Indian Ocean, consistent with a ''warmest get wetter'' mechanism. Over land subtropical drying is relatively robust, particularly in the early wet season. This has contributions from dynamical shifts in the location of convection, which may be related to regional SST structures in the southern Indian Ocean, and the thermodynamic decline in relative humidity. Implications for understanding and potentially constraining uncertainty in projections are discussed. © 2018 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/111531
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: Department of Geography, University of Sussex, Brighton, United Kingdom; Met Office Hadley Centre, Exeter, United Kingdom
Recommended Citation:
Lazenby M.J.,Todd M.C.,Chadwick R.,et al. Future precipitation projections over central and Southern Africa and the adjacent Indian Ocean: What causes the changes and the uncertainty?[J]. Journal of Climate,2018-01-01,31(12)