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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:19/0  |  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.


  
Distributed Acoustic Sensing of Seismic Properties in a Borehole Drilled on a Fast-Flowing Greenlandic Outlet Glacier 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (13)
作者:  Booth, Adam D.;  Christoffersen, Poul;  Schoonman, Charlotte;  Clarke, Andy;  Hubbard, Bryn;  Law, Robert;  Doyle, Samuel H.;  Chudley, Thomas R.;  Chalari, Athena
收藏  |  浏览/下载:10/0  |  提交时间:2020/06/09
Distributed Acoustic Sensing (DAS)  Vertical Seismic Profile (VSP)  Greenland Ice Sheet  anisotropy  subglacial sediment  borehole surveying  
Extending the Global Mass Change Data Record: GRACE Follow-On Instrument and Science Data Performance 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (12)
作者:  Landerer, Felix W.;  Flechtner, Frank M.;  Save, Himanshu;  Webb, Frank H.;  Bandikova, Tamara;  Bertiger, William, I;  Bettadpur, Srinivas, V;  Byun, Sung Hun;  Dahle, Christoph;  Dobslaw, Henryk;  Fahnestock, Eugene;  Harvey, Nate;  Kang, Zhigui;  Kruizinga, Gerhard L. H.;  Loomis, Bryant D.;  McCullough, Christopher;  Murboeck, Michael;  Nagel, Peter;  Paik, Meegyeong;  Pie, Nadege;  Poole, Steve;  Strekalov, Dmitry;  Tamisiea, Mark E.;  Wang, Furun;  Watkins, Michael M.;  Wen, Hui-Ying;  Wiese, David N.;  Yuan, Dah-Ning
收藏  |  浏览/下载:12/0  |  提交时间:2020/05/25
GRACE-FO  satellite gravimetry  mass change  hydrogeodesy  ice melt  mass transport  
Bathymetry Beneath Ice Shelves of Western Dronning Maud Land, East Antarctica, and Implications on Ice Shelf Stability 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (12)
作者:  Eisermann, Hannes;  Eagles, Graeme;  Ruppel, Antonia;  Smith, Emma Clare;  Jokat, Wilfried
收藏  |  浏览/下载:7/0  |  提交时间:2020/05/13
subglacial topography  bathymetry model  gravity inversion  Fimbul  Jelbart  Ekstrom  
Continuity of Ice Sheet Mass Loss in Greenland and Antarctica From the GRACE and GRACE Follow-On Missions 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (8)
作者:  Velicogna, Isabella;  Mohajerani, Yara;  Geruo, A.;  Landerer, Felix;  Mouginot, Jeremie;  Noel, Brice;  Rignot, Eric;  Sutterley, Tyler;  van den Broeke, Michiel;  Wessem, Melchior;  Wiese, David
收藏  |  浏览/下载:9/0  |  提交时间:2020/07/02
Antarctica  Greenland  GRACE  mass balance  climate change  glaciology  
Eurasian Ice Sheet collapse was a major source of Meltwater Pulse 1A 14,600 years ago 期刊论文
NATURE GEOSCIENCE, 2020, 13 (5)
作者:  Brendryen, Jo;  Haflidason, Haflidi;  Yokoyama, Yusuke;  Haaga, Kristian Agasoster;  Hannisdal, Bjarte
收藏  |  浏览/下载:9/0  |  提交时间:2020/05/13
Ancient ice-sheet collapse 期刊论文
NATURE GEOSCIENCE, 2020, 13 (5) : 328-329
作者:  Ortiz, Joseph D.
收藏  |  浏览/下载:1/0  |  提交时间:2020/05/13
Wind-Driven Evolution of the North Pacific Subpolar Gyre Over the Last Deglaciation 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (6)
作者:  Gray, William R.;  Wills, Robert C. J.;  Rae, James W. B.;  Burke, Andrea;  Ivanovic, Ruza F.;  Roberts, William H. G.;  Ferreira, David;  Valdes, Paul J.
收藏  |  浏览/下载:8/0  |  提交时间:2020/07/02
North Pacific  deglaciation  gyre circulation  westerlies  oxygen isotopes  climate models  
Englacial Architecture and Age-Depth Constraints Across the West Antarctic Ice Sheet 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (6)
作者:  Ashmore, David W.;  Bingham, Robert G.;  Ross, Neil;  Siegert, Martin;  Jordan, Tom A.;  Mair, Douglas W. F.
收藏  |  浏览/下载:5/0  |  提交时间:2020/07/02
Ice penetrating radar  Englacial stratigraphy  West Antarctica  Radio echo sounding  Holocene  AntArchitecture  
The Brewer-Dobson Circulation During the Last Glacial Maximum 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (5)
作者:  Fu, Qiang;  White, Rachel H.;  Wang, Mingcheng;  Alexander, Becky;  Solomon, Susan;  Gettelman, Andrew;  Battisti, David S.;  Lin, Pu
收藏  |  浏览/下载:8/0  |  提交时间:2020/07/02