DOI: 10.5194/cp-9-1417-2013
Scopus记录号: 2-s2.0-84881152316
论文题名: Megalake chad impact on climate and vegetation during the late Pliocene and the mid-Holocene
作者: Contoux C. ; Jost A. ; Ramstein G. ; Sepulchre P. ; Krinner G. ; Schuster M.
刊名: Climate of the Past
ISSN: 18149324
出版年: 2013
卷: 9, 期: 4 起始页码: 1417
结束页码: 1430
语种: 英语
Scopus关键词: climate change
; evaporation
; habitat type
; Holocene
; hominid
; lake
; numerical model
; paleoclimate
; Pliocene
; precipitation (climatology)
; vegetation structure
; Chad Basin
英文摘要: Given the growing evidence for megalakes in the geological record, assessing their impact on climate and vegetation is important for the validation of palaeoclimate simulations and therefore the accuracy of model-data comparison in lacustrine environments. Megalake Chad (MLC) occurrences are documented not only for the mid-Holocene but also for the Mio-Pliocene (Schuster et al., 2009). At this time, the surface covered by water would have reached up to ∼350 000 km2 (Ghienne et al., 2002; Schuster et al., 2005; Leblanc et al., 2006), making it an important evaporation source, possibly modifying climate and vegetation in the Chad Basin. We investigated the impact of such a giant continental water area in two different climatic backgrounds within the Paleoclimate Model Intercomparison Project phase 3 (PMIP3): the late Pliocene (3.3 to 3 Ma, i.e. the mid-Piacenzian warm period) and the mid-Holocene (6 kyr BP). In all simulations including MLC, precipitation is drastically reduced above the lake surface because deep convection is inhibited by overlying colder air. Meanwhile, convective activity is enhanced around MLC because of the wind increase generated by the flat surface of the megalake, transporting colder and moister air towards the eastern shore of the lake. The effect of MLC on precipitation and temperature is not sufficient to widely impact vegetation patterns. Nevertheless, tropical savanna is present in the Chad Basin in all climatic configurations, even without MLC presence, showing that the climate itself is the driver of favourable environments for sustainable hominid habitats. © 2013 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/49421
Appears in Collections: 气候变化与战略
There are no files associated with this item.
Recommended Citation:
Contoux C.,Jost A.,Ramstein G.,et al. Megalake chad impact on climate and vegetation during the late Pliocene and the mid-Holocene[J]. Climate of the Past,2013-01-01,9(4)