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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: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.


  
Seasonal predictions initialised by assimilating sea surface temperature observations with the EnKF 期刊论文
CLIMATE DYNAMICS, 2019, 53: 5777-5797
作者:  Wang, Yiguo;  Counillon, Francois;  Keenlyside, Noel;  Svendsen, Lea;  Gleixner, Stephanie;  Kimmritz, Madlen;  Dai, Panxi;  Gao, Yongqi
收藏  |  浏览/下载:7/0  |  提交时间:2019/11/27
Seasonal prediction  Advanced data assimilation  EnKF  SST  NorCPM  ENSO  Sea ice extent  
Detecting the statistical significance of the trends in the Antarctic sea ice extent: an indication for a turning point 期刊论文
CLIMATE DYNAMICS, 2019, 53: 237-244
作者:  Ludescher, Josef;  Yuan, Naiming;  Bunde, Armin
收藏  |  浏览/下载:4/0  |  提交时间:2019/11/26
Antarctica  Sea ice extent  Natural variability  
Assessing uncertainties in sea ice extent climate indicators 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2019, 14 (3)
作者:  Meier, Walter N.;  Stewart, J. Scott
收藏  |  浏览/下载:4/0  |  提交时间:2019/04/09
sea ice  sea ice extent  Arctic  Antarctic  remote sensing  passive microwave  climate change indicator  
An ocean-sea ice model study of the unprecedented Antarctic sea ice minimum in 2016 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2018, 13 (8)
作者:  Kusahara, Kazuya;  Reid, Phillip;  Williams, Guy D.;  Massom, Robert;  Hasumi, Hiroyasu
收藏  |  浏览/下载:4/0  |  提交时间:2019/04/09
Antarctic sea ice  ocean-sea ice modeling  the minimum sea ice extent in 2016  
Inter- and intra-annual changes in air temperature and precipitation in western Spitsbergen 期刊论文
INTERNATIONAL JOURNAL OF CLIMATOLOGY, 2017, 37 (7)
作者:  Osuch, Marzena;  Wawrzyniak, Tomasz
收藏  |  浏览/下载:4/0  |  提交时间:2019/04/09
Arctic  Spitsbergen  Hornsund  climate variation  climatic indices  NAO  sea ice extent  
Antarctic sea ice change based on a new sea ice dataset from 1992 to 2008 期刊论文
CLIMATE RESEARCH, 2017, 71 (2)
作者:  He, Li-Yin;  Ke, Chang-Qing;  Zhou, Xiaobing;  Cui, Ya-Nan;  Shan, Liang
收藏  |  浏览/下载:5/0  |  提交时间:2019/04/09
SICCI algorithm  Sea ice extent  Sea ice area  Sea surface temperature  Antarctica