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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.


  
Source forensics ofn-alkanes andn-fatty acids in urban aerosols using compound specific radiocarbon/stable carbon isotopic composition 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (7)
作者:  Ren, Lujie;  Wang, Yiyun;  Kawamura, Kimitaka;  Bikkina, Srinivas;  Haghipour, Negar;  Wacker, Lukas;  Pavuluri, Chandra Mouli;  Zhang, Zhimin;  Yue, Siyao;  Sun, Yele;  Wang, Zifa;  Zhang, Yanli;  Feng, Xiaojuan;  Liu, Cong-Qiang;  Eglinton, Timothy, I;  Fu, Pingqing
收藏  |  浏览/下载:15/0  |  提交时间:2020/08/18
atmospheric aerosols  n-alkanes  n-fatty acids  compound-specific stable carbon isotopes  radiocarbon isotopes  
Changes of Emission Sources to Nitrate Aerosols in Beijing After the Clean Air Actions: Evidence From Dual Isotope Compositions 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (12)
作者:  Fan, Mei-Yi;  Zhang, Yan-Lin;  Lin, Yu-Chi;  Cao, Fang;  Zhao, Zhu-Yu;  Sun, Yele;  Qiu, Yanmei;  Fu, Pingqing;  Wang, Yuxuan
收藏  |  浏览/下载:13/0  |  提交时间:2020/08/18
nitrate aerosols  haze events  stable isotopes  formation mechanism  source apportionment  
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:7/0  |  提交时间:2020/07/02
chamber  evapotranspiration partitioning  leaf area index  soil water content  stable isotopes  Tibetan Plateau  
Long-term ecological consequences of forest fires in the continuous permafrost zone of Siberia 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (3)
作者:  Kirdyanov, Alexander, V;  Saurer, Matthias;  Siegwolf, Rolf;  Knorre, Anastasia A.;  Prokushkin, Anatoly S.;  (Sidorova), Olga V. Churakova;  Fonti, Marina, V;  Buentgen, Ulf
收藏  |  浏览/下载:14/0  |  提交时间:2020/07/02
active soil layer  boreal forest  permafrost  Siberia  stable isotopes  tree rings  wildfire  
Isotopic evidence for quasi-equilibrium chemistry in thermally mature natural gases 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (8) : 3989-3995
作者:  Thiagarajan, Nivedita;  Xie, Hao;  Ponton, Camilo;  Kitchen, Nami;  Peterson, Brian;  Lawson, Michael;  Formolo, Michael;  Xiao, Yitian;  Eiler, John
收藏  |  浏览/下载:7/0  |  提交时间:2020/05/13
stable isotopes  compound-specific isotope analysis  clumped isotopes  natural gas  methane  
Trophic niche segregation allows range-extending coral reef fishes to co-exist with temperate species under climate change 期刊论文
GLOBAL CHANGE BIOLOGY, 2019
作者:  Kingsbury, Kelsey M.;  Gillanders, Bronwyn M.;  Booth, David J.;  Nagelkerken, Ivan
收藏  |  浏览/下载:14/0  |  提交时间:2020/02/17
diet  niche use  ocean warming  range shifts  stable isotopes  
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:7/0  |  提交时间:2019/11/27
Agroecology  antibiotics  ecosystem function  elemental cycles  microbial ecology  stable isotopes