DOI: 10.5194/cp-9-1761-2013
Scopus记录号: 2-s2.0-84881464099
论文题名: Assessing the impact of late Pleistocene megafaunal extinctions on global vegetation and climate
作者: Brault M.-O. ; Mysak L.A. ; Matthews H.D. ; Simmons C.T.
刊名: Climate of the Past
ISSN: 18149324
出版年: 2013
卷: 9, 期: 4 起始页码: 1761
结束页码: 1771
语种: 英语
Scopus关键词: albedo
; assessment method
; carbon cycle
; climate effect
; climate modeling
; deglaciation
; glaciation
; herbivore
; mammoth
; mass extinction
; Pleistocene
; reforestation
; soil carbon
英文摘要: The end of the Pleistocene was a turning point for the Earth system as climate gradually emerged from millennia of severe glaciation in the Northern Hemisphere. The deglacial climate change coincided with an unprecedented decline in many species of Pleistocene megafauna, including the near-total eradication of the woolly mammoth. Due to an herbivorous diet that presumably involved large-scale tree grazing, the mammoth extinction has been associated with the rapid expansion of dwarf deciduous trees in Siberia and Beringia, thus potentially contributing to the changing climate of the period. In this study, we use the University of Victoria Earth System Climate Model (UVic ESCM) to simulate the possible effects of these extinctions on climate during the latest deglacial period. We have explored various hypothetical scenarios of forest expansion in the northern high latitudes, quantifying the biogeophysical effects in terms of changes in surface albedo and air temperature. These scenarios include a Maximum Impact Scenario (MIS) which simulates the greatest possible post-extinction reforestation in the model, and sensitivity tests which investigate the timing of extinction, the fraction of trees grazed by mammoths, and the southern extent of mammoth habitats. We also show the results of a simulation with free atmospheric CO2-carbon cycle interactions. For the MIS, we obtained a surface albedo increase and global warming of 0.006 and 0.175 C, respectively. Less extreme scenarios produced smaller global mean temperature changes, though local warming in some locations exceeded 0.3 C even in the more realistic extinction scenarios. In the free CO2 simulation, the biogeophysical-induced warming was amplified by a biogeochemical effect, whereby the replacement of high-latitude tundra with shrub forest led to a release of soil carbon to the atmosphere and a small atmospheric CO2 increase. Overall, our results suggest the potential for a small, though non-trivial, effect of megafaunal extinctions on Pleistocene climate.© Author(s) 2013. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/49413
Appears in Collections: 气候变化与战略
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Recommended Citation:
Brault M.-O.,Mysak L.A.,Matthews H.D.,et al. Assessing the impact of late Pleistocene megafaunal extinctions on global vegetation and climate[J]. Climate of the Past,2013-01-01,9(4)