Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates
A major tipping point of Earth's history occurred during the mid-Pliocene: the onset of major Northern-Hemisphere Glaciation (NHG) and of pronounced, Quaternary-style cycles of glacial-to-interglacial climates, that contrast with more uniform climates over most of the preceding Cenozoic and con...
Main Authors: | , , , , , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus
2009
|
Subjects: | |
Online Access: | https://hdl.handle.net/20.500.11850/19019 https://doi.org/10.3929/ethz-b-000019019 |
id |
ftethz:oai:www.research-collection.ethz.ch:20.500.11850/19019 |
---|---|
record_format |
openpolar |
spelling |
ftethz:oai:www.research-collection.ethz.ch:20.500.11850/19019 2023-05-15T13:11:46+02:00 Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates Sarnthein, Michael Bartoli, Gretta Prange, Matthias Schmittner, Andreas Schneider, Birgit Weinelt, M. Andersen, Nils Garbe-Schönberg, Dieter 2009 application/application/pdf https://hdl.handle.net/20.500.11850/19019 https://doi.org/10.3929/ethz-b-000019019 en eng Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/cp-5-269-2009 http://hdl.handle.net/20.500.11850/19019 doi:10.3929/ethz-b-000019019 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/3.0/ Creative Commons Attribution 3.0 Unported CC-BY Climate of the Past, 5 (2) info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2009 ftethz https://doi.org/20.500.11850/19019 https://doi.org/10.3929/ethz-b-000019019 https://doi.org/10.5194/cp-5-269-2009 2022-04-25T13:50:26Z A major tipping point of Earth's history occurred during the mid-Pliocene: the onset of major Northern-Hemisphere Glaciation (NHG) and of pronounced, Quaternary-style cycles of glacial-to-interglacial climates, that contrast with more uniform climates over most of the preceding Cenozoic and continue until today (Zachos et al., 2001). The severe deterioration of climate occurred in three steps between 3.2 Ma (warm MIS K3) and 2.7 Ma (glacial MIS G6/4) (Lisiecki and Raymo, 2005). Various models (sensu Driscoll and Haug, 1998) and paleoceanographic records (intercalibrated using orbital age control) suggest clear linkages between the onset of NHG and the three steps in the final closure of the Central American Seaways (CAS), deduced from rising salinity differences between Caribbean and the East Pacific. Each closing event led to an enhanced North Atlantic meridional overturning circulation and this strengthened the poleward transport of salt and heat (warmings of +2–3°C) (Bartoli et al., 2005). Also, the closing resulted in a slight rise in the poleward atmospheric moisture transport to northwestern Eurasia (Lunt et al., 2007), which probably led to an enhanced precipitation and fluvial run-off, lower sea surface salinity (SSS), and an increased sea-ice cover in the Arctic Ocean, hence promoting albedo and the build-up of continental ice sheets. Most important, new evidence shows that the closing of the CAS led to greater steric height of the North Pacific and thus doubled the low-saline Arctic Throughflow from the Bering Strait to the East Greenland Current (EGC). Accordingly, Labrador Sea IODP Site 1307 displays an abrupt but irreversible EGC cooling of 6°C and freshening by ~2 psu from 3.25/3.16–3.00 Ma, right after the first but still reversible attempt of closing the CAS. ISSN:1814-9324 ISSN:1814-9332 Article in Journal/Newspaper albedo Arctic Arctic Ocean Bering Strait East Greenland east greenland current Greenland Labrador Sea North Atlantic Sea ice ETH Zürich Research Collection Arctic Arctic Ocean Bering Strait Greenland Haug ENVELOPE(15.188,15.188,67.918,67.918) Pacific |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
description |
A major tipping point of Earth's history occurred during the mid-Pliocene: the onset of major Northern-Hemisphere Glaciation (NHG) and of pronounced, Quaternary-style cycles of glacial-to-interglacial climates, that contrast with more uniform climates over most of the preceding Cenozoic and continue until today (Zachos et al., 2001). The severe deterioration of climate occurred in three steps between 3.2 Ma (warm MIS K3) and 2.7 Ma (glacial MIS G6/4) (Lisiecki and Raymo, 2005). Various models (sensu Driscoll and Haug, 1998) and paleoceanographic records (intercalibrated using orbital age control) suggest clear linkages between the onset of NHG and the three steps in the final closure of the Central American Seaways (CAS), deduced from rising salinity differences between Caribbean and the East Pacific. Each closing event led to an enhanced North Atlantic meridional overturning circulation and this strengthened the poleward transport of salt and heat (warmings of +2–3°C) (Bartoli et al., 2005). Also, the closing resulted in a slight rise in the poleward atmospheric moisture transport to northwestern Eurasia (Lunt et al., 2007), which probably led to an enhanced precipitation and fluvial run-off, lower sea surface salinity (SSS), and an increased sea-ice cover in the Arctic Ocean, hence promoting albedo and the build-up of continental ice sheets. Most important, new evidence shows that the closing of the CAS led to greater steric height of the North Pacific and thus doubled the low-saline Arctic Throughflow from the Bering Strait to the East Greenland Current (EGC). Accordingly, Labrador Sea IODP Site 1307 displays an abrupt but irreversible EGC cooling of 6°C and freshening by ~2 psu from 3.25/3.16–3.00 Ma, right after the first but still reversible attempt of closing the CAS. ISSN:1814-9324 ISSN:1814-9332 |
format |
Article in Journal/Newspaper |
author |
Sarnthein, Michael Bartoli, Gretta Prange, Matthias Schmittner, Andreas Schneider, Birgit Weinelt, M. Andersen, Nils Garbe-Schönberg, Dieter |
spellingShingle |
Sarnthein, Michael Bartoli, Gretta Prange, Matthias Schmittner, Andreas Schneider, Birgit Weinelt, M. Andersen, Nils Garbe-Schönberg, Dieter Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates |
author_facet |
Sarnthein, Michael Bartoli, Gretta Prange, Matthias Schmittner, Andreas Schneider, Birgit Weinelt, M. Andersen, Nils Garbe-Schönberg, Dieter |
author_sort |
Sarnthein, Michael |
title |
Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates |
title_short |
Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates |
title_full |
Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates |
title_fullStr |
Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates |
title_full_unstemmed |
Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates |
title_sort |
mid-pliocene shifts in ocean overturning circulation and the onset of quaternary-style climates |
publisher |
Copernicus |
publishDate |
2009 |
url |
https://hdl.handle.net/20.500.11850/19019 https://doi.org/10.3929/ethz-b-000019019 |
long_lat |
ENVELOPE(15.188,15.188,67.918,67.918) |
geographic |
Arctic Arctic Ocean Bering Strait Greenland Haug Pacific |
geographic_facet |
Arctic Arctic Ocean Bering Strait Greenland Haug Pacific |
genre |
albedo Arctic Arctic Ocean Bering Strait East Greenland east greenland current Greenland Labrador Sea North Atlantic Sea ice |
genre_facet |
albedo Arctic Arctic Ocean Bering Strait East Greenland east greenland current Greenland Labrador Sea North Atlantic Sea ice |
op_source |
Climate of the Past, 5 (2) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/cp-5-269-2009 http://hdl.handle.net/20.500.11850/19019 doi:10.3929/ethz-b-000019019 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/3.0/ Creative Commons Attribution 3.0 Unported |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/20.500.11850/19019 https://doi.org/10.3929/ethz-b-000019019 https://doi.org/10.5194/cp-5-269-2009 |
_version_ |
1766248891806646272 |