气候变化领域集成服务门户(CCPortal): Brief communication: New radar constraints support presence of ice older than 1.5 Myr at Little Dome C

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DOI	10.5194/tc-15-1881-2021
	Brief communication: New radar constraints support presence of ice older than 1.5 Myr at Little Dome C
	Lilien D.A.; Steinhage D.; Taylor D.; Parrenin F.; Ritz C.; Mulvaney R.; Martín C.; Yan J.-B.; O'Neill C.; Frezzotti M.; Miller H.; Gogineni P.; Dahl-Jensen D.; Eisen O.
发表日期	2021
ISSN	19940416
起始页码	1881
结束页码	1888
卷号	15 期号:4
英文摘要	The area near Dome C, East Antarctica, is thought to be one of the most promising targets for recovering a continuous ice-core record spanning more than a million years. The European Beyond EPICA consortium has selected Little Dome C (LDC), an area ∼35 km southeast of Concordia Station, to attempt to recover such a record. Here, we present the results of the final ice-penetrating radar survey used to refine the exact drill site. These data were acquired during the 2019-2020 austral summer using a new, multi-channel highresolution very high frequency (VHF) radar operating in the frequency range of 170-230 MHz. This new instrument is able to detect reflectors in the near-basal region, where previous surveys were largely unable to detect horizons. The radar stratigraphy is used to transfer the timescale of the EPICA Dome C ice core (EDC) to the area of Little Dome C, using radar isochrones dating back past 600 ka. We use these data to derive the expected depth-age relationship through the ice column at the now-chosen drill site, termed BELDC (Beyond EPICA LDC). These new data indicate that the ice at BELDC is considerably older than that at EDC at the same depth and that there is about 375m of ice older than 600 kyr at BELDC. Stratigraphy is well preserved to 2565 m, ∼93% of the ice thickness, below which there is a basal unit with unknown properties. An ice-flow model tuned to the isochrones suggests ages likely reach 1.5 Myr near 2500 m, ∼65m above the basal unit and ∼265m above the bed, with sufficient resolution (19±2 kyrm-1) to resolve 41 kyr glacial cycles. © Author(s) 2021.
英文关键词	detection method; ice core; ice cover; radar; Antarctica; Dome Concordia; East Antarctica
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202363
作者单位	Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark; Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, Bremerhaven, Germany; Remote Sensing Center, University of Alabama, Tuscaloosa, AL, United States; Institut des Géosciences de l'Environnement, University Grenoble Alpes, CNRS, IRD, IGE, Grenoble, France; British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom; Department of Science, University Roma Tre, Rome, Italy; Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, Canada; Department of Geosciences, University of Bremen, Bremen, Germany
推荐引用方式 GB/T 7714	Lilien D.A.,Steinhage D.,Taylor D.,et al. Brief communication: New radar constraints support presence of ice older than 1.5 Myr at Little Dome C[J],2021,15(4).
APA	Lilien D.A..,Steinhage D..,Taylor D..,Parrenin F..,Ritz C..,...&Eisen O..(2021).Brief communication: New radar constraints support presence of ice older than 1.5 Myr at Little Dome C.Cryosphere,15(4).
MLA	Lilien D.A.,et al."Brief communication: New radar constraints support presence of ice older than 1.5 Myr at Little Dome C".Cryosphere 15.4(2021).