North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles
Variations in the ratio of magnesium to calcium (Mg/Ca) in fossil ostracodes from Deep Sea Drilling Project Site 607 in the deep North Atlantic show that the change in bottom water temperature during late Pliocene 41,000-year obliquity cycles averaged 1.5°C between 3.2 and 2.8 million years ago (Ma)...
Main Authors: | , , , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
American Association for the Advancement of Science (AAAS)
1995
|
Subjects: | |
Online Access: | https://hdl.handle.net/10161/6997 |
id |
ftdukeunivdsp:oai:localhost:10161/6997 |
---|---|
record_format |
openpolar |
spelling |
ftdukeunivdsp:oai:localhost:10161/6997 2023-11-12T04:05:01+01:00 North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles Dwyer, GS Cronin, TM Baker, PA Raymo, ME Buzas, JS Corrège, T 1995-12-01 application/pdf https://hdl.handle.net/10161/6997 unknown American Association for the Advancement of Science (AAAS) Science 0036-8075 https://hdl.handle.net/10161/6997 Journal article 1995 ftdukeunivdsp 2023-10-17T09:46:13Z Variations in the ratio of magnesium to calcium (Mg/Ca) in fossil ostracodes from Deep Sea Drilling Project Site 607 in the deep North Atlantic show that the change in bottom water temperature during late Pliocene 41,000-year obliquity cycles averaged 1.5°C between 3.2 and 2.8 million years ago (Ma) and increased to 2.3°C between 2.8 and 2.3 Ma, coincidentally with the intensification of Northern Hemisphere glaciation. During the last two 100,000-year glacial-to-interglacial climatic cycles of the Quaternary, bottom water temperatures changed by 4.5°C. These results show that glacial deepwater cooling has intensified since 3.2 Ma, most likely as the result of progressively diminished deep-water production in the North Atlantic and of the greater influence of Antarctic bottom water in the North Atlantic during glacial periods. The ostracode Mg/Ca data also allow the direct determination of the temperature component of the benthic foraminiferal oxygen isotope record from Site 607, as well as derivation of a hypothetical sea-level curve for the late Pliocene and late Quaternary. The effects of dissolution on the Mg/Ca ratios of ostracode shells appear to have been minimal. Article in Journal/Newspaper Antarc* Antarctic North Atlantic Duke University Libraries: DukeSpace Antarctic |
institution |
Open Polar |
collection |
Duke University Libraries: DukeSpace |
op_collection_id |
ftdukeunivdsp |
language |
unknown |
description |
Variations in the ratio of magnesium to calcium (Mg/Ca) in fossil ostracodes from Deep Sea Drilling Project Site 607 in the deep North Atlantic show that the change in bottom water temperature during late Pliocene 41,000-year obliquity cycles averaged 1.5°C between 3.2 and 2.8 million years ago (Ma) and increased to 2.3°C between 2.8 and 2.3 Ma, coincidentally with the intensification of Northern Hemisphere glaciation. During the last two 100,000-year glacial-to-interglacial climatic cycles of the Quaternary, bottom water temperatures changed by 4.5°C. These results show that glacial deepwater cooling has intensified since 3.2 Ma, most likely as the result of progressively diminished deep-water production in the North Atlantic and of the greater influence of Antarctic bottom water in the North Atlantic during glacial periods. The ostracode Mg/Ca data also allow the direct determination of the temperature component of the benthic foraminiferal oxygen isotope record from Site 607, as well as derivation of a hypothetical sea-level curve for the late Pliocene and late Quaternary. The effects of dissolution on the Mg/Ca ratios of ostracode shells appear to have been minimal. |
format |
Article in Journal/Newspaper |
author |
Dwyer, GS Cronin, TM Baker, PA Raymo, ME Buzas, JS Corrège, T |
spellingShingle |
Dwyer, GS Cronin, TM Baker, PA Raymo, ME Buzas, JS Corrège, T North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
author_facet |
Dwyer, GS Cronin, TM Baker, PA Raymo, ME Buzas, JS Corrège, T |
author_sort |
Dwyer, GS |
title |
North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
title_short |
North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
title_full |
North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
title_fullStr |
North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
title_full_unstemmed |
North atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
title_sort |
north atlantic deepwater temperature change during late pliocene and late quaternary climatic cycles |
publisher |
American Association for the Advancement of Science (AAAS) |
publishDate |
1995 |
url |
https://hdl.handle.net/10161/6997 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic North Atlantic |
genre_facet |
Antarc* Antarctic North Atlantic |
op_relation |
Science 0036-8075 https://hdl.handle.net/10161/6997 |
_version_ |
1782341839078031360 |