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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:18/0  |  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.


  
On the Relationship Between the Marine Cold Air Outbreak M Parameter and Low-Level Cloud Heights in the Midlatitudes 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (13)
作者:  Naud, Catherine M.;  Booth, James F.;  Lamer, Katia;  Marchand, Roger;  Protat, Alain;  McFarquhar, Greg M.
收藏  |  浏览/下载:11/0  |  提交时间:2020/08/18
low-level clouds  southern ocean  MCAO M-index  CAM6  boundary layer stability  
Zonal Similarity of Long-Term Changes and Seasonal Cycles of Baseline Ozone at Northern Midlatitudes 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (13)
作者:  Parrish, David D.;  Derwent, Richard G.;  Steinbrecht, Wolfgang;  Stuebi, Rene;  Van Malderen, Roeland;  Steinbacher, Martin;  Trickl, Thomas;  Ries, Ludwig;  Xu, Xiaobin
收藏  |  浏览/下载:12/0  |  提交时间:2020/08/18
baseline ozone  long-term changes  seasonal cycle  zonal similarity  ozone maximum  
The Orinoco Low-Level Jet: An Investigation of Its Mechanisms of Formation Using the WRF Model 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (13)
作者:  Jimenez-Sanchez, Giovanni;  Markowski, Paul M.;  Young, George S.;  Stensrud, David J.
收藏  |  浏览/下载:9/0  |  提交时间:2020/08/18
Orinoco low-level jet  forcing mechanisms  dynamical downscaling  momentum balance analysis  LLJs near the equator may originate from processes other than the inertial oscillation  LLJs near the equator may originate from processes other than topographic thermal forcing  
Influence of Multiscale Orography on the Initiation and Maintenance of a Precipitating Convective System in North China: A Case Study 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (13)
作者:  Hua, Shaofeng;  Xu, Xin;  Chen, Baojun
收藏  |  浏览/下载:8/0  |  提交时间:2020/08/18
orographic precipitation  gravity waves  mountain-plain solenoidal  multiscale topography  North China  
Diurnal Cycle of Precipitation Over the Maritime Continent Under Modulation of MJO: Perspectives From Cloud-Permitting Scale Simulations 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (13)
作者:  Wei, Yuntao;  Pu, Zhaoxia;  Zhang, Chidong
收藏  |  浏览/下载:8/0  |  提交时间:2020/08/18
tropical convection  diurnal cycle of precipitation  cloud-permitting simulation  MJO  
Warming trends increasingly dominate global ocean 期刊论文
NATURE CLIMATE CHANGE, 2020
作者:  Johnson, Gregory C.;  Lyman, John M.
收藏  |  浏览/下载:7/0  |  提交时间:2020/07/21
Sea spray aerosol organic enrichment, water uptake and surface tension effects 期刊论文
ATMOSPHERIC CHEMISTRY AND PHYSICS, 2020, 20 (13) : 7955-7977
作者:  Cravigan, Luke T.;  Mallet, Marc D.;  Vaattovaara, Petri;  Harvey, Mike J.;  Law, Cliff S.;  Modini, Robin L.;  Russell, Lynn M.;  Stelcer, Ed;  Cohen, David D.;  Olsen, Greg;  Safi, Karl;  Burrell, Timothy J.;  Ristovski, Zoran
收藏  |  浏览/下载:10/0  |  提交时间:2020/07/14
Mud in rivers transported as flocculated and suspended bed material 期刊论文
NATURE GEOSCIENCE, 2020
作者:  Lamb, Michael P.;  de Leeuw, Jan;  Fischer, Woodward W.;  Moodie, Andrew J.;  Venditti, Jeremy G.;  Nittrouer, Jeffrey A.;  Haught, Daniel;  Parker, Gary
收藏  |  浏览/下载:11/0  |  提交时间:2020/07/09
Adaptation time to magnified flood hazards underestimated when derived from tide gauge records 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (7)
作者:  Lambert, Erwin;  Rohmer, Jeremy;  Le Cozannet, Goneri;  van de Wal, Roderik S. W.
收藏  |  浏览/下载:7/0  |  提交时间:2020/08/18
Sea-level rise  extreme water level  waves  coastal adaptation  joint probability