Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records
The Bering Sea gateway between the Pacific and Arctic oceans impacts global climate when glacial-interglacial shifts in shore line position and ice coverage change regional albedo. Previous work has shown that during the last glacial termination and into the Holocene, sea level rises and sea ice cov...
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ftunivmassamh:oai:works.bepress.com:julie_brigham_grette-1025 2023-05-15T13:11:57+02:00 Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records Cassie, Beth E Brigham_Grette, Julie Lawrence, Kira T Herbert, Timothy D Cook, Mea S 2010-02-09T08:00:00Z https://works.bepress.com/julie_brigham_grette/13 unknown SelectedWorks https://works.bepress.com/julie_brigham_grette/13 Julie Brigham-Grette Bering Sea diatoms alkenones Earth Sciences Glaciology text 2010 ftunivmassamh 2022-01-09T20:24:06Z The Bering Sea gateway between the Pacific and Arctic oceans impacts global climate when glacial-interglacial shifts in shore line position and ice coverage change regional albedo. Previous work has shown that during the last glacial termination and into the Holocene, sea level rises and sea ice coverage diminishes from perennial to absent. Yet, existing work has not quantified sea ice duration or sea surface temperatures (SST) during this transition. Here we combine diatom assemblages with the first alkenone record from the Bering Sea to provide a semiquantitative record of sea ice duration, SST, and productivity change since the Last Glacial Maximum (LGM). During the LGM, diatom assemblages indicate that sea ice covered the southeastern Bering Sea perennially. At 15.1 cal ka B.P., the diatom assemblage shifts to one more characteristic of seasonal sea ice and alkenones occur in the sediments in low concentrations. Deglaciation is characterized by laminated intervals with highly productive and diverse diatom assemblages and inferred high coccolithophorid production. At 11.3 cal ka B.P. the diatom assemblage shifts from one dominated by sea ice species to one dominated by a warmer water, North Pacific species. Simultaneously, the SST increases by 3°C and the southeastern Bering Sea becomes ice-free year-round. Productivity and temperature proxies are positively correlated with independently dated records from elsewhere in the Bering Sea, the Sea of Okhotsk, and the North Pacific, indicating that productivity and SST changes are coeval across the region. Text albedo Arctic Bering Sea Sea ice University of Massachusetts: ScholarWorks@UMass Amherst Arctic Bering Sea Okhotsk Pacific Umnak Plateau ENVELOPE(-170.250,-170.250,54.250,54.250) |
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Open Polar |
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University of Massachusetts: ScholarWorks@UMass Amherst |
op_collection_id |
ftunivmassamh |
language |
unknown |
topic |
Bering Sea diatoms alkenones Earth Sciences Glaciology |
spellingShingle |
Bering Sea diatoms alkenones Earth Sciences Glaciology Cassie, Beth E Brigham_Grette, Julie Lawrence, Kira T Herbert, Timothy D Cook, Mea S Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records |
topic_facet |
Bering Sea diatoms alkenones Earth Sciences Glaciology |
description |
The Bering Sea gateway between the Pacific and Arctic oceans impacts global climate when glacial-interglacial shifts in shore line position and ice coverage change regional albedo. Previous work has shown that during the last glacial termination and into the Holocene, sea level rises and sea ice coverage diminishes from perennial to absent. Yet, existing work has not quantified sea ice duration or sea surface temperatures (SST) during this transition. Here we combine diatom assemblages with the first alkenone record from the Bering Sea to provide a semiquantitative record of sea ice duration, SST, and productivity change since the Last Glacial Maximum (LGM). During the LGM, diatom assemblages indicate that sea ice covered the southeastern Bering Sea perennially. At 15.1 cal ka B.P., the diatom assemblage shifts to one more characteristic of seasonal sea ice and alkenones occur in the sediments in low concentrations. Deglaciation is characterized by laminated intervals with highly productive and diverse diatom assemblages and inferred high coccolithophorid production. At 11.3 cal ka B.P. the diatom assemblage shifts from one dominated by sea ice species to one dominated by a warmer water, North Pacific species. Simultaneously, the SST increases by 3°C and the southeastern Bering Sea becomes ice-free year-round. Productivity and temperature proxies are positively correlated with independently dated records from elsewhere in the Bering Sea, the Sea of Okhotsk, and the North Pacific, indicating that productivity and SST changes are coeval across the region. |
format |
Text |
author |
Cassie, Beth E Brigham_Grette, Julie Lawrence, Kira T Herbert, Timothy D Cook, Mea S |
author_facet |
Cassie, Beth E Brigham_Grette, Julie Lawrence, Kira T Herbert, Timothy D Cook, Mea S |
author_sort |
Cassie, Beth E |
title |
Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records |
title_short |
Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records |
title_full |
Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records |
title_fullStr |
Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records |
title_full_unstemmed |
Last Glacial Maximum to Holocene sea surface conditions at Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable isotope records |
title_sort |
last glacial maximum to holocene sea surface conditions at umnak plateau, bering sea, as inferred from diatom, alkenone, and stable isotope records |
publisher |
SelectedWorks |
publishDate |
2010 |
url |
https://works.bepress.com/julie_brigham_grette/13 |
long_lat |
ENVELOPE(-170.250,-170.250,54.250,54.250) |
geographic |
Arctic Bering Sea Okhotsk Pacific Umnak Plateau |
geographic_facet |
Arctic Bering Sea Okhotsk Pacific Umnak Plateau |
genre |
albedo Arctic Bering Sea Sea ice |
genre_facet |
albedo Arctic Bering Sea Sea ice |
op_source |
Julie Brigham-Grette |
op_relation |
https://works.bepress.com/julie_brigham_grette/13 |
_version_ |
1766249693066559488 |