Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming
We investigate the stability of the East Antarctic Ice Sheet (EAIS) on the Wilkes Land continental margin, Antarctica, utilizing a high‐resolution record of ice‐rafted debris (IRD) mass accumulation rates (MAR) from Integrated Ocean Drilling Program Site U1359. The relationship between orbital varia...
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ftmontclairstuni:oai:digitalcommons.montclair.edu:earth-environ-studies-facpubs-1037 2023-07-23T04:14:25+02:00 Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming Hansen, Melissa A. Passchier, Sandra Khim, Boo‐Keun Song, Buhan Williams, Trevor 2015-05-26T07:00:00Z application/pdf https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/39 https://digitalcommons.montclair.edu/context/earth-environ-studies-facpubs/article/1037/viewcontent/Hansen_et_al_2015_Paleoceanography.pdf unknown Montclair State University Digital Commons https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/39 https://digitalcommons.montclair.edu/context/earth-environ-studies-facpubs/article/1037/viewcontent/Hansen_et_al_2015_Paleoceanography.pdf Department of Earth and Environmental Studies Faculty Scholarship and Creative Works iceberg discharges east Antarctic Ice Sheet Geology Glaciology text 2015 ftmontclairstuni 2023-07-03T21:42:22Z We investigate the stability of the East Antarctic Ice Sheet (EAIS) on the Wilkes Land continental margin, Antarctica, utilizing a high‐resolution record of ice‐rafted debris (IRD) mass accumulation rates (MAR) from Integrated Ocean Drilling Program Site U1359. The relationship between orbital variations in the IRD record and climate drivers was evaluated to capture changes in the dynamics of a marine‐based ice sheet in response to early Pliocene warming. Three IRD MAR excursions were observed and confirmed via scanning electron microscope microtextural analysis of sand grains. Time series analysis of the IRD MAR reveals obliquity‐paced expansions of the ice sheet to the outer shelf prior to ~4.6 Ma. A decline in the obliquity and a transition into a dominant precession response of IRD MAR occur at ~4.6 Ma along with a decline in the amplitude of IRD MAR maxima to low background levels between ~4.0 and ~3.5 Ma. We speculate that as sea surface temperatures began to peak above 3°C during the early Pliocene climatic optimum, the ice shelves thinned, leading to a greater susceptibility to precession‐forced summer insolation and the onset of persistent retreat of a marine‐based portion of the EAIS. Text Antarc* Antarctic Antarctica Ice Sheet Ice Shelves Iceberg* Wilkes Land Montclair State University Digital Commons Antarctic East Antarctic Ice Sheet Wilkes Land ENVELOPE(120.000,120.000,-69.000,-69.000) |
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iceberg discharges east Antarctic Ice Sheet Geology Glaciology |
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iceberg discharges east Antarctic Ice Sheet Geology Glaciology Hansen, Melissa A. Passchier, Sandra Khim, Boo‐Keun Song, Buhan Williams, Trevor Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming |
topic_facet |
iceberg discharges east Antarctic Ice Sheet Geology Glaciology |
description |
We investigate the stability of the East Antarctic Ice Sheet (EAIS) on the Wilkes Land continental margin, Antarctica, utilizing a high‐resolution record of ice‐rafted debris (IRD) mass accumulation rates (MAR) from Integrated Ocean Drilling Program Site U1359. The relationship between orbital variations in the IRD record and climate drivers was evaluated to capture changes in the dynamics of a marine‐based ice sheet in response to early Pliocene warming. Three IRD MAR excursions were observed and confirmed via scanning electron microscope microtextural analysis of sand grains. Time series analysis of the IRD MAR reveals obliquity‐paced expansions of the ice sheet to the outer shelf prior to ~4.6 Ma. A decline in the obliquity and a transition into a dominant precession response of IRD MAR occur at ~4.6 Ma along with a decline in the amplitude of IRD MAR maxima to low background levels between ~4.0 and ~3.5 Ma. We speculate that as sea surface temperatures began to peak above 3°C during the early Pliocene climatic optimum, the ice shelves thinned, leading to a greater susceptibility to precession‐forced summer insolation and the onset of persistent retreat of a marine‐based portion of the EAIS. |
format |
Text |
author |
Hansen, Melissa A. Passchier, Sandra Khim, Boo‐Keun Song, Buhan Williams, Trevor |
author_facet |
Hansen, Melissa A. Passchier, Sandra Khim, Boo‐Keun Song, Buhan Williams, Trevor |
author_sort |
Hansen, Melissa A. |
title |
Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming |
title_short |
Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming |
title_full |
Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming |
title_fullStr |
Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming |
title_full_unstemmed |
Threshold Behavior of a Marine‐based Sector of the East Antarctic Ice Sheet in Response to Early Pliocene Ocean Warming |
title_sort |
threshold behavior of a marine‐based sector of the east antarctic ice sheet in response to early pliocene ocean warming |
publisher |
Montclair State University Digital Commons |
publishDate |
2015 |
url |
https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/39 https://digitalcommons.montclair.edu/context/earth-environ-studies-facpubs/article/1037/viewcontent/Hansen_et_al_2015_Paleoceanography.pdf |
long_lat |
ENVELOPE(120.000,120.000,-69.000,-69.000) |
geographic |
Antarctic East Antarctic Ice Sheet Wilkes Land |
geographic_facet |
Antarctic East Antarctic Ice Sheet Wilkes Land |
genre |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelves Iceberg* Wilkes Land |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Ice Shelves Iceberg* Wilkes Land |
op_source |
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works |
op_relation |
https://digitalcommons.montclair.edu/earth-environ-studies-facpubs/39 https://digitalcommons.montclair.edu/context/earth-environ-studies-facpubs/article/1037/viewcontent/Hansen_et_al_2015_Paleoceanography.pdf |
_version_ |
1772184724970668032 |