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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:21/0  |  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.


  
Quantifying the Controls on Evapotranspiration Partitioning in the Highest Alpine Meadow Ecosystem 期刊论文
WATER RESOURCES RESEARCH, 2020, 56 (4)
作者:  Cui, Jiangpeng;  Tian, Lide;  Wei, Zhongwang;  Huntingford, Chris;  Wang, Pei;  Cai, Zhongyin;  Ma, Ning;  Wang, Lixin
收藏  |  浏览/下载:10/0  |  提交时间:2020/07/02
chamber  evapotranspiration partitioning  leaf area index  soil water content  stable isotopes  Tibetan Plateau  
Catchment Travel Times From Composite StorAge Selection Functions Representing the Superposition of Streamflow Generation Processes 期刊论文
WATER RESOURCES RESEARCH, 2019
作者:  Rodriguez, Nicolas B.;  Klaus, Julian
收藏  |  浏览/下载:7/0  |  提交时间:2020/02/16
stable isotopes  superposition of processes  catchment travel time  StorAge Selection functions  runoff generation  multimodal distribution  
Water-use efficiency in a semi-arid woodland with high rainfall variability 期刊论文
GLOBAL CHANGE BIOLOGY, 2019
作者:  Tarin, Tonantzin;  Nolan, Rachael H.;  Medlyn, Belinda E.;  Cleverly, James;  Eamus, Derek
收藏  |  浏览/下载:8/0  |  提交时间:2019/11/27
Acacia  Australia  carbon flux  eddy covariance  optimal stomatal behaviour  photosynthesis  stable isotopes  
Prolonged exposure to manure from livestock-administered antibiotics decreases ecosystem carbon-use efficiency and alters nitrogen cycling 期刊论文
ECOLOGY LETTERS, 2019
作者:  Wepking, Carl;  Badgley, Brian;  Barrett, John E.;  Knowlton, Katharine F.;  Lucas, Jane M.;  Minick, Kevan J.;  Ray, Partha P.;  Shawver, Sarah E.;  Strickland, Michael S.
收藏  |  浏览/下载:9/0  |  提交时间:2019/11/27
Agroecology  antibiotics  ecosystem function  elemental cycles  microbial ecology  stable isotopes  
Stable isotopes are quantitative indicators of trophic niche 期刊论文
ECOLOGY LETTERS, 2019, 22 (11) : 1990-1992
作者:  Marshall, Harry H.;  Inger, Richard;  Jackson, Andrew L.;  McDonald, Robbie A.;  Thompson, Faye J.;  Cant, Michael A.
收藏  |  浏览/下载:6/0  |  提交时间:2019/11/27
Banded mongoose  diet  isotopic niche  niche overlap  stable isotopes  tissue integration time  trophic niche  
Adapt or die-Response of large herbivores to environmental changes in Europe during the Holocene 期刊论文
GLOBAL CHANGE BIOLOGY, 2019, 25 (9) : 2915-2930
作者:  Hofman-Kaminska, Emilia;  Bocherens, Herve;  Drucker, Dorothee G.;  Fyfe, Ralph M.;  Guminski, Witold;  Makowiecki, Daniel;  Pacher, Martina;  Piliciauskiene, Giedre;  Samojlik, Tomasz;  Woodbridge, Jessie;  Kowalczyk, Rafal
收藏  |  浏览/下载:13/0  |  提交时间:2019/11/27
Alces alces  aurochs  Bison bonasus  Bos primigenius  European bison  foraging ecology  moose  stable isotopes  
Effects of Reforestation of a Degraded Imperata Grassland on Dominant Flow Pathways and Streamflow Responses in Leyte, the Philippines 期刊论文
WATER RESOURCES RESEARCH, 2019, 55 (5) : 4128-4148
作者:  van Meerveld, H. J. (Ilja);  Zhang, Jun;  Tripoli, Roger;  Bruijnzeel, L. Adrian
收藏  |  浏览/下载:9/0  |  提交时间:2019/11/26
tropical reforestation  runoff generation mechanisms  hydrograph separation  electrical conductivity  stable isotopes  space-for-time substitution  
Stratification, nitrogen fixation, and cyanobacterial bloom stage regulate the planktonic food web structure 期刊论文
GLOBAL CHANGE BIOLOGY, 2019, 25 (3) : 794-810
作者:  Loick-Wilde, Natalie;  Fernandez-Urruzola, Igor;  Eglite, Elvita;  Liskow, Iris;  Nausch, Monika;  Schulz-Bull, Detlef;  Wodarg, Dirk;  Wasmund, Norbert;  Mohrholz, Volker
收藏  |  浏览/下载:7/0  |  提交时间:2019/04/09
amino acids  Baltic Sea  bloom stage  cyanobacteria  food web structure  mesozooplankton  N-2 fixation  stable nitrogen isotopes  stratification  
North America's oldest boreal trees are more efficient water users due to increased [CO2], but do not grow faster 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2019, 116 (7) : 2749-2754
作者:  Giguere-Croteau, Claudie;  Boucher, Etienne;  Bergeron, Yves;  Girardin, Martin P.;  Drobyshev, Igor;  Silva, Lucas C. R.;  Helie, Jean-Francois;  Garneau, Michelle
收藏  |  浏览/下载:12/0  |  提交时间:2019/11/27
water use efficiency  carbon dioxide  stable isotopes  productivity  boreal forest