气候变化领域集成服务门户(CCPortal): Dynamic Antarctic ice sheet during the early to mid-Miocene

CCPortal

DOI	10.1073/pnas.1516130113
	Dynamic Antarctic ice sheet during the early to mid-Miocene
	Gasson E.; DeConto R.M.; Pollard D.; Levy R.H.
发表日期	2016
ISSN	0027-8424
起始页码	3459
结束页码	3464
卷号	113 期号:13
英文摘要	Geological data indicate that there were major variations in Antarctic ice sheet volume and extent during the early to mid-Miocene. Simulating such large-scale changes is problematic because of a strong hysteresis effect, which results in stability once the ice sheets have reached continental size. A relatively narrow range of atmospheric CO2 concentrations indicated by proxy records exacerbates this problem. Here, we are able to simulate large-scale variability of the early to mid-Miocene Antarctic ice sheet because of three developments in our modeling approach. (i) We use a climate-ice sheet coupling method utilizing a high-resolution atmospheric component to account for ice sheet-climate feedbacks. (ii) The ice sheet model includes recently proposed mechanisms for retreat into deep subglacial basins caused by ice-cliff failure and ice-shelf hydrofracture. (iii)We account for changes in the oxygen isotopic composition of the ice sheet by using isotope-enabled climate and ice sheet models. We compare our modeling results with ice-proximal records emerging from a sedimentological drill core from the Ross Sea (Andrill-2A) that is presented in a companion article. The variability in Antarctic ice volume that we simulate is equivalent to a seawater oxygen isotope signal of 0.52-0.66‰, or a sea level equivalent change of 30-36 m, for a range of atmospheric CO2 between 280 and 500 ppm and a changing astronomical configuration. This result represents a substantial advance in resolving the long-standing model data conflict of Miocene Antarctic ice sheet and sea level variability.
英文关键词	Antarctic ice sheet; Miocene; Oxygen isotopes; Sea level
语种	英语
scopus关键词	carbon dioxide; oxygen; sea water; Antarctica; Article; astronomy; climate; continental shelf; glaciation; ice sheet; ice shelf; Lower Miocene; Middle Miocene; priority journal; sea level; vegetation
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/158905
作者单位	Gasson, E., Climate System Research Center, University of Massachusetts, Amherst, MA 01003, United States; DeConto, R.M., Climate System Research Center, University of Massachusetts, Amherst, MA 01003, United States; Pollard, D., Earth and Environmental Systems Institute, Pennsylvania State University, State College, PA 16802, United States; Levy, R.H., GNS Science, Avalon, Lower Hutt, 5011, New Zealand
推荐引用方式 GB/T 7714	Gasson E.,DeConto R.M.,Pollard D.,et al. Dynamic Antarctic ice sheet during the early to mid-Miocene[J],2016,113(13).
APA	Gasson E.,DeConto R.M.,Pollard D.,&Levy R.H..(2016).Dynamic Antarctic ice sheet during the early to mid-Miocene.Proceedings of the National Academy of Sciences of the United States of America,113(13).
MLA	Gasson E.,et al."Dynamic Antarctic ice sheet during the early to mid-Miocene".Proceedings of the National Academy of Sciences of the United States of America 113.13(2016).