Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability
<p>The S27 ice core, drilled in the Allan Hills Blue Ice Area of East Antarctica, is located in southern Victoria Land, <span class="inline-formula">∼80</span> km away from the present-day northern edge of the Ross Ice Shelf. Here, we utilize the reconstructed accumulatio...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2021-09-01
|
| Series: | Climate of the Past |
| Online Access: | https://cp.copernicus.org/articles/17/1841/2021/cp-17-1841-2021.pdf |
| _version_ | 1819123331846111232 |
|---|---|
| author | Y. Yan Y. Yan N. E. Spaulding M. L. Bender M. L. Bender E. J. Brook J. A. Higgins A. V. Kurbatov P. A. Mayewski |
| author_facet | Y. Yan Y. Yan N. E. Spaulding M. L. Bender M. L. Bender E. J. Brook J. A. Higgins A. V. Kurbatov P. A. Mayewski |
| author_sort | Y. Yan |
| collection | DOAJ |
| description | <p>The S27 ice core, drilled in the Allan Hills Blue Ice
Area of East Antarctica, is located in southern Victoria Land, <span class="inline-formula">∼80</span> km away from the present-day northern edge of the Ross
Ice Shelf. Here, we utilize the reconstructed accumulation rate of S27
covering the Last Interglacial (LIG) period between 129 ka and 116 ka (where ka indicates thousands of years before present) to infer moisture transport into the region. The
accumulation rate is based on the ice-age–gas-age differences calculated
from the ice chronology, which is constrained by the stable water isotopes
of the ice, and an improved gas chronology based on measurements of oxygen
isotopes of <span class="inline-formula">O<sub>2</sub></span> in the trapped gases. The peak accumulation rate in S27
occurred at 128.2 ka, near the peak LIG warming in Antarctica. Even the most
conservative estimate yields an order-of-magnitude increase in the
accumulation rate during the LIG maximum, whereas other Antarctic ice cores
are typically characterized by a glacial–interglacial difference of a factor
of 2 to 3. While part of the increase in S27 accumulation rates must
originate from changes in the large-scale atmospheric circulation,
additional mechanisms are needed to explain the large changes. We
hypothesize that the exceptionally high snow accumulation recorded in S27
reflects open-ocean conditions in the Ross Sea, created by reduced sea ice
extent and increased polynya size and perhaps by a southward retreat of the
Ross Ice Shelf relative to its present-day position near the onset of the LIG.
The proposed ice shelf retreat would also be compatible with a sea-level
high stand around 129 ka significantly sourced from West Antarctica. The
peak in S27 accumulation rates is transient, suggesting that if the Ross Ice
Shelf had indeed retreated during the early LIG, it would have re-advanced
by 125 ka.</p> |
| first_indexed | 2024-12-22T07:06:39Z |
| format | Article |
| id | doaj.art-2b2fb888413f410f9b1bf070260ff06c |
| institution | Directory Open Access Journal |
| issn | 1814-9324 1814-9332 |
| language | English |
| last_indexed | 2024-12-22T07:06:39Z |
| publishDate | 2021-09-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Climate of the Past |
| spelling | doaj.art-2b2fb888413f410f9b1bf070260ff06c2022-12-21T18:34:38ZengCopernicus PublicationsClimate of the Past1814-93241814-93322021-09-01171841185510.5194/cp-17-1841-2021Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stabilityY. Yan0Y. Yan1N. E. Spaulding2M. L. Bender3M. L. Bender4E. J. Brook5J. A. Higgins6A. V. Kurbatov7P. A. Mayewski8Department of Geosciences, Princeton University, Princeton, NJ 08544, USADepartment of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005, USAClimate Change Institute, University of Maine, Orono, ME 04469, USADepartment of Geosciences, Princeton University, Princeton, NJ 08544, USASchool of Oceanography, Shanghai Jiao Tong University, Shanghai 200240, ChinaCollege of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USADepartment of Geosciences, Princeton University, Princeton, NJ 08544, USAClimate Change Institute, University of Maine, Orono, ME 04469, USAClimate Change Institute, University of Maine, Orono, ME 04469, USA<p>The S27 ice core, drilled in the Allan Hills Blue Ice Area of East Antarctica, is located in southern Victoria Land, <span class="inline-formula">∼80</span> km away from the present-day northern edge of the Ross Ice Shelf. Here, we utilize the reconstructed accumulation rate of S27 covering the Last Interglacial (LIG) period between 129 ka and 116 ka (where ka indicates thousands of years before present) to infer moisture transport into the region. The accumulation rate is based on the ice-age–gas-age differences calculated from the ice chronology, which is constrained by the stable water isotopes of the ice, and an improved gas chronology based on measurements of oxygen isotopes of <span class="inline-formula">O<sub>2</sub></span> in the trapped gases. The peak accumulation rate in S27 occurred at 128.2 ka, near the peak LIG warming in Antarctica. Even the most conservative estimate yields an order-of-magnitude increase in the accumulation rate during the LIG maximum, whereas other Antarctic ice cores are typically characterized by a glacial–interglacial difference of a factor of 2 to 3. While part of the increase in S27 accumulation rates must originate from changes in the large-scale atmospheric circulation, additional mechanisms are needed to explain the large changes. We hypothesize that the exceptionally high snow accumulation recorded in S27 reflects open-ocean conditions in the Ross Sea, created by reduced sea ice extent and increased polynya size and perhaps by a southward retreat of the Ross Ice Shelf relative to its present-day position near the onset of the LIG. The proposed ice shelf retreat would also be compatible with a sea-level high stand around 129 ka significantly sourced from West Antarctica. The peak in S27 accumulation rates is transient, suggesting that if the Ross Ice Shelf had indeed retreated during the early LIG, it would have re-advanced by 125 ka.</p>https://cp.copernicus.org/articles/17/1841/2021/cp-17-1841-2021.pdf |
| spellingShingle | Y. Yan Y. Yan N. E. Spaulding M. L. Bender M. L. Bender E. J. Brook J. A. Higgins A. V. Kurbatov P. A. Mayewski Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability Climate of the Past |
| title | Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability |
| title_full | Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability |
| title_fullStr | Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability |
| title_full_unstemmed | Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability |
| title_short | Enhanced moisture delivery into Victoria Land, East Antarctica, during the early Last Interglacial: implications for West Antarctic Ice Sheet stability |
| title_sort | enhanced moisture delivery into victoria land east antarctica during the early last interglacial implications for west antarctic ice sheet stability |
| url | https://cp.copernicus.org/articles/17/1841/2021/cp-17-1841-2021.pdf |
| work_keys_str_mv | AT yyan enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT yyan enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT nespaulding enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT mlbender enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT mlbender enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT ejbrook enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT jahiggins enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT avkurbatov enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability AT pamayewski enhancedmoisturedeliveryintovictorialandeastantarcticaduringtheearlylastinterglacialimplicationsforwestantarcticicesheetstability |