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Laurentide ice saddle mergers drive rapid sea level drops during glaciations 期刊论文
Geophysical Research Letters, 2021
作者:  Weiwen Ji;  Alexander Robel;  Eli Tziperman;  Jun Yang
收藏  |  浏览/下载:7/0  |  提交时间:2021/07/27
Phasing of millennial-scale climate variability in the Pacific and Atlantic Oceans 期刊论文
Science, 2020
作者:  Maureen H. Walczak;  Alan C. Mix;  Ellen A. Cowan;  Stewart Fallon;  L. Keith Fifield;  Jay R. Alder;  Jianghui Du;  Brian Haley;  Tim Hobern;  June Padman;  Summer K. Praetorius;  Andreas Schmittner;  Joseph S. Stoner;  Sarah D. Zellers
收藏  |  浏览/下载:11/0  |  提交时间:2020/11/09
Steering iceberg armadas 期刊论文
Science, 2020
作者:  John M. Jaeger;  Amelia E. Shevenell
收藏  |  浏览/下载:7/0  |  提交时间:2020/11/09
Ice retreat in Wilkes Basin of East Antarctica during a warm interglacial 期刊论文
NATURE, 2020, 583 (7817) : 554-+
作者:  T. Blackburn;  G. H. Edwards;  S. Tulaczyk;  M. Scudder;  G. Piccione;  B. Hallet;  N. McLean;  J. C. Zachos;  B. Cheney;  J. T. Babbe
收藏  |  浏览/下载:20/0  |  提交时间:2020/08/09

Uranium isotopes in subglacial precipitates from the Wilkes Basin of the East Antarctic Ice Sheet reveal ice retreat during a warm Pleistocene interglacial period about 400,000 years ago.


Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth'  s past interglacial warm periods(1-3). About 400,000 years ago, during the interglacial period known as Marine Isotopic Stage 11 (MIS11), the global temperature was 1 to 2 degrees Celsius greater(2)and sea level was 6 to 13 metres higher(1,3). Sea level estimates in excess of about 10 metres, however, have been discounted because these require a contribution from the East Antarctic Ice Sheet(3), which has been argued to have remained stable for millions of years before and includes MIS11(4,5). Here we show how the evolution of(234)U enrichment within the subglacial waters of East Antarctica recorded the ice sheet'  s response to MIS11 warming. Within the Wilkes Basin, subglacial chemical precipitates of opal and calcite record accumulation of(234)U (the product of rock-water contact within an isolated subglacial reservoir) up to 20 times higher than that found in marine waters. The timescales of(234)U enrichment place the inception of this reservoir at MIS11. Informed by the(234)U cycling observed in the Laurentide Ice Sheet, where(234)U accumulated during periods of ice stability(6)and was flushed to global oceans in response to deglaciation(7), we interpret our East Antarctic dataset to represent ice loss within the Wilkes Basin at MIS11. The(234)U accumulation within the Wilkes Basin is also observed in the McMurdo Dry Valleys brines(8-10), indicating(11)that the brine originated beneath the adjacent East Antarctic Ice Sheet. The marine origin of brine salts(10)and bacteria(12)implies that MIS11 ice loss was coupled with marine flooding. Collectively, these data indicate that during one of the warmest Pleistocene interglacials, the ice sheet margin at the Wilkes Basin retreated to near the precipitate location, about 700 kilometres inland from the current position of the ice margin, which-assuming current ice volumes-would have contributed about 3 to 4 metres(13)to global sea levels.


  
300,000 yr history of water-table fluctuations at Wind Cave, South Dakota, USA-Scale, timing, and groundwater mixing in the Madison Aquifer 期刊论文
GEOLOGICAL SOCIETY OF AMERICA BULLETIN, 2020, 132 (7-8) : 1447-1468
作者:  Paces, James B.;  Palmer, Margaret, V;  Palmer, Arthur N.;  Long, Andrew J.;  Emmons, Matthew P.
收藏  |  浏览/下载:10/0  |  提交时间:2020/08/18
Early Holocene Temperature Oscillations Exceed Amplitude of Observed and Projected Warming in Svalbard Lakes 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019
作者:  van der Bilt, Willem G. M.;  39;Andrea, William J.
收藏  |  浏览/下载:9/0  |  提交时间:2020/02/17
alkenone  Arctic  paleoclimate  Quaternary  Holocene  lake sediments  
Leveraging the Rapid Retreat of the Amundsen Gulf Ice Stream 13,000 Years Ago to Reveal Insight Into North American Deglaciation 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (21) : 12101-12107
作者:  Pico, T.;  Robel, A.;  Powell, E.;  Mix, A. C.;  Mitrovica, J. X.
收藏  |  浏览/下载:5/0  |  提交时间:2020/02/17
Glacial isostatic adjustment  Marine ice sheet instability  Deglaciation  Ice stream  Laurentide Ice Sheet  
Applying the Community Ice Sheet Model to evaluate PMIP3 LGM climatologies over the North American ice sheets 期刊论文
CLIMATE DYNAMICS, 2019, 53: 2807-2824
作者:  Alder, Jay R.;  Hostetler, Steven W.
收藏  |  浏览/下载:7/0  |  提交时间:2019/11/27
PMIP3  LGM  Model evaluation  CISM2  Ice sheet modeling  
Erosion rates and sediment flux within the Potomac River basin quantified over millennial timescales using beryllium isotopes 期刊论文
GEOLOGICAL SOCIETY OF AMERICA BULLETIN, 2019, 131: 1295-1311
作者:  Portenga, Eric W.;  Bierman, Paul R.;  Trodick, Charles D., Jr.;  Greene, Sophie E.;  DeJong, Benjamin D.;  Rood, Dylan H.;  Pavich, Milan J.
收藏  |  浏览/下载:6/0  |  提交时间:2019/11/27
A Model for the Formation of Eskers 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (12) : 6673-6680
作者:  Hewitt, Ian J.;  Creyts, Timothy T.
收藏  |  浏览/下载:4/0  |  提交时间:2019/11/26
esker  subglacial landforms  mathematical model  deglaciation