气候变化领域集成服务门户(CCPortal): Warm fjords and vegetated landscapes in early Pliocene East Antarctica

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DOI	10.1016/j.epsl.2019.116045
	Warm fjords and vegetated landscapes in early Pliocene East Antarctica
	Ohneiser C.; Wilson G.S.; Beltran C.; Dolan A.M.; Hill D.J.; Prebble J.G.
发表日期	2020
ISSN	0012821X
卷号	534
英文摘要	The response of the Antarctic ice sheets to future warming is uncertain. The IPCC are predicting minimal melt from Antarctica while others suggest increased meltwater contributions are possible. The Pliocene period (5.333 Ma to 2.58 Ma) may provide insights into future ice sheet response, because atmospheric CO2 concentrations were similar to today (350-450 ppmv) and the earth surface was between 2 °C and 4 °C warmer than the preindustrial conditions. Geological records indicate that Antarctica's ice sheets were smaller and more dynamic at this time and many sea-level estimates require meltwater input from the Greenland, West (WAIS) and East Antarctic Ice sheets (EAIS). However, only a few records exist proximal to the Antarctic ice sheet which allow for reconstruction of the Pliocene climate state. We present a multiproxy climate reconstruction from a sedimentary succession that was deposited in an ancient fjord within the Transantarctic Mountains, covering discrete intervals between the early Pliocene and the late Pleistocene. In contrast to modern frigid conditions, our records indicate sea surface temperatures of about 5.6 °C at c. 4.1 Ma, the presence of a plant community at the fjord margins and evidence of soil formation. Simulations of potential vegetation cover in the Pliocene indicate our reconstruction is most compatible with a complete collapse of the WAIS and a large scale retreat of the EAIS from the subglacial basins with atmospheric CO2 levels of less than 450 ppmv. Our study indicates that under present day atmospheric CO2 conditions, in the early Pliocene, the Antarctic ice sheets retreated significantly. Understanding the mechanisms driving this large-scale ice sheet retreat would enable us to assess whether current atmospheric CO2 concentrations will lead to the same ice sheet configuration once the Earth system has come to a new equilibrium state. © 2019 Elsevier B.V.
关键词	BIOME4 East Antarctic Ice Sheet environmental magnetism modelling Pliocene sedimentary biomarkers
英文关键词	Carbon dioxide; Glaciers; Models; Plants (botany); Sea level; Sedimentology; Surface waters; BIOME4; Climate reconstruction; East antarctic ice sheets; Environmental magnetism; Pliocene; Pre-industrial conditions; Sea surface temperature (SST); Vegetated landscapes; Ice; biomarker; carbon dioxide; fjord; ice sheet; paleoclimate; Pliocene; proxy climate record; sea level; vegetation cover; Antarctic Ice Sheet; Antarctica; Arctic; East Antarctic Ice Sheet; East Antarctica; Greenland; Greenland Ice Sheet
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202813
作者单位	Department of Geology, University of Otago, P.O. Box 56, Dunedin, New Zealand; Department of Marine Science, University of Otago, P.O. Box 56, Dunedin, New Zealand; Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand; School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, United Kingdom; GNS Science, 1 Fairway Drive, Avalon, Lower Hutt, 5010, New Zealand
推荐引用方式 GB/T 7714	Ohneiser C.,Wilson G.S.,Beltran C.,et al. Warm fjords and vegetated landscapes in early Pliocene East Antarctica[J],2020,534.
APA	Ohneiser C.,Wilson G.S.,Beltran C.,Dolan A.M.,Hill D.J.,&Prebble J.G..(2020).Warm fjords and vegetated landscapes in early Pliocene East Antarctica.Earth and Planetary Science Letters,534.
MLA	Ohneiser C.,et al."Warm fjords and vegetated landscapes in early Pliocene East Antarctica".Earth and Planetary Science Letters 534(2020).