The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference
The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ∼68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here...
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Online Access: | https://doi.org/10.5194/cp-11-153-2015 https://cp.copernicus.org/articles/11/153/2015/ |
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ftcopernicus:oai:publications.copernicus.org:cp26552 2023-05-15T13:54:27+02:00 The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference Buizert, C. Cuffey, K. M. Severinghaus, J. P. Baggenstos, D. Fudge, T. J. Steig, E. J. Markle, B. R. Winstrup, M. Rhodes, R. H. Brook, E. J. Sowers, T. A. Clow, G. D. Cheng, H. Edwards, R. L. Sigl, M. McConnell, J. R. Taylor, K. C. 2018-10-02 application/pdf https://doi.org/10.5194/cp-11-153-2015 https://cp.copernicus.org/articles/11/153/2015/ eng eng doi:10.5194/cp-11-153-2015 https://cp.copernicus.org/articles/11/153/2015/ eISSN: 1814-9332 Text 2018 ftcopernicus https://doi.org/10.5194/cp-11-153-2015 2020-07-20T16:24:47Z The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ∼68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8–31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age–ice age difference (Δage) using a combination of firn densification modeling, ice-flow modeling, and a data set of δ 15 N-N 2 , a proxy for past firn column thickness. The largest Δage at WD occurs during the Last Glacial Maximum, and is 525 ± 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard–Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Δage at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the "bipolar seesaw". Text Antarc* Antarctic Greenland Greenland ice core Greenland ice cores ice core Ice Sheet Copernicus Publications: E-Journals Antarctic Greenland Hulu ENVELOPE(8.610,8.610,62.837,62.837) West Antarctic Ice Sheet Climate of the Past 11 2 153 173 |
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Open Polar |
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Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ∼68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8–31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age–ice age difference (Δage) using a combination of firn densification modeling, ice-flow modeling, and a data set of δ 15 N-N 2 , a proxy for past firn column thickness. The largest Δage at WD occurs during the Last Glacial Maximum, and is 525 ± 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard–Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Δage at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the "bipolar seesaw". |
format |
Text |
author |
Buizert, C. Cuffey, K. M. Severinghaus, J. P. Baggenstos, D. Fudge, T. J. Steig, E. J. Markle, B. R. Winstrup, M. Rhodes, R. H. Brook, E. J. Sowers, T. A. Clow, G. D. Cheng, H. Edwards, R. L. Sigl, M. McConnell, J. R. Taylor, K. C. |
spellingShingle |
Buizert, C. Cuffey, K. M. Severinghaus, J. P. Baggenstos, D. Fudge, T. J. Steig, E. J. Markle, B. R. Winstrup, M. Rhodes, R. H. Brook, E. J. Sowers, T. A. Clow, G. D. Cheng, H. Edwards, R. L. Sigl, M. McConnell, J. R. Taylor, K. C. The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference |
author_facet |
Buizert, C. Cuffey, K. M. Severinghaus, J. P. Baggenstos, D. Fudge, T. J. Steig, E. J. Markle, B. R. Winstrup, M. Rhodes, R. H. Brook, E. J. Sowers, T. A. Clow, G. D. Cheng, H. Edwards, R. L. Sigl, M. McConnell, J. R. Taylor, K. C. |
author_sort |
Buizert, C. |
title |
The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference |
title_short |
The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference |
title_full |
The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference |
title_fullStr |
The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference |
title_full_unstemmed |
The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference |
title_sort |
wais divide deep ice core wd2014 chronology – part 1: methane synchronization (68–31 ka bp) and the gas age–ice age difference |
publishDate |
2018 |
url |
https://doi.org/10.5194/cp-11-153-2015 https://cp.copernicus.org/articles/11/153/2015/ |
long_lat |
ENVELOPE(8.610,8.610,62.837,62.837) |
geographic |
Antarctic Greenland Hulu West Antarctic Ice Sheet |
geographic_facet |
Antarctic Greenland Hulu West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Greenland Greenland ice core Greenland ice cores ice core Ice Sheet |
genre_facet |
Antarc* Antarctic Greenland Greenland ice core Greenland ice cores ice core Ice Sheet |
op_source |
eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-11-153-2015 https://cp.copernicus.org/articles/11/153/2015/ |
op_doi |
https://doi.org/10.5194/cp-11-153-2015 |
container_title |
Climate of the Past |
container_volume |
11 |
container_issue |
2 |
container_start_page |
153 |
op_container_end_page |
173 |
_version_ |
1766260356681826304 |