Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka
Here we report 420 kyr long records of sediment geochemical and color variations from the southwestern Iberian Margin. We synchronized the Iberian Margin sediment record to Antarctic ice cores and speleothem records on millennial time scales and investigated the phase responses relative to orbital f...
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ftnerc:oai:nora.nerc.ac.uk:502220 2023-05-15T13:48:07+02:00 Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka Hodell, David Crowhurst, Simon Skinner, Luke Tzedakis, Polychronis C. Margari, Vasiliki Channell, James E.T. Kamenov, George Maclachlan, Suzanne Rothwell, Guy 2013-03 text http://nora.nerc.ac.uk/id/eprint/502220/ https://nora.nerc.ac.uk/id/eprint/502220/1/palo20017_Hodell.pdf https://doi.org/10.1002/palo.20017 en eng https://nora.nerc.ac.uk/id/eprint/502220/1/palo20017_Hodell.pdf Hodell, David; Crowhurst, Simon; Skinner, Luke; Tzedakis, Polychronis C.; Margari, Vasiliki; Channell, James E.T.; Kamenov, George; Maclachlan, Suzanne; Rothwell, Guy. 2013 Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka. Paleoceanography, 28 (1). 185-199. https://doi.org/10.1002/palo.20017 <https://doi.org/10.1002/palo.20017> Publication - Article PeerReviewed 2013 ftnerc https://doi.org/10.1002/palo.20017 2023-02-04T19:37:08Z Here we report 420 kyr long records of sediment geochemical and color variations from the southwestern Iberian Margin. We synchronized the Iberian Margin sediment record to Antarctic ice cores and speleothem records on millennial time scales and investigated the phase responses relative to orbital forcing of multiple proxy records available from these cores. Iberian Margin sediments contain strong precession power. Sediment “redness” (a* and 570–560 nm) and the ratio of long-chain alcohols to n-alkanes (C26OH/(C26OH + C29)) are highly coherent and in-phase with precession. Redder layers and more oxidizing conditions (low alcohol ratio) occur near precession minima (summer insolation maxima). We suggest these proxies respond rapidly to low-latitude insolation forcing by wind-driven processes (e.g., dust transport, upwelling, precipitation). Most Iberian Margin sediment parameters lag obliquity maxima by 7–8 ka, indicating a consistent linear response to insolation forcing at obliquity frequencies driven mainly by high-latitude processes. Although the lengths of the time series are short (420 ka) for detecting 100 kyr eccentricity cycles, the phase relationships support those obtained by Shackleton []. Antarctic temperature and the Iberian Margin alcohol ratios (C26OH/(C26OH + C29)) lead eccentricity maxima by 6 kyr, with lower ratios (increased oxygenation) occurring at eccentricity maxima. CO2, CH4, and Iberian SST are nearly in phase with eccentricity, and minimum ice volume (as inferred from Pacific δ18Oseawater) lags eccentricity maxima by 10 kyr. The phase relationships derived in this study continue to support a potential role of the Earth's carbon cycle in contributing to the 100 kyr cycle. Article in Journal/Newspaper Antarc* Antarctic Natural Environment Research Council: NERC Open Research Archive Antarctic Shackleton Pacific Paleoceanography 28 1 185 199 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
Here we report 420 kyr long records of sediment geochemical and color variations from the southwestern Iberian Margin. We synchronized the Iberian Margin sediment record to Antarctic ice cores and speleothem records on millennial time scales and investigated the phase responses relative to orbital forcing of multiple proxy records available from these cores. Iberian Margin sediments contain strong precession power. Sediment “redness” (a* and 570–560 nm) and the ratio of long-chain alcohols to n-alkanes (C26OH/(C26OH + C29)) are highly coherent and in-phase with precession. Redder layers and more oxidizing conditions (low alcohol ratio) occur near precession minima (summer insolation maxima). We suggest these proxies respond rapidly to low-latitude insolation forcing by wind-driven processes (e.g., dust transport, upwelling, precipitation). Most Iberian Margin sediment parameters lag obliquity maxima by 7–8 ka, indicating a consistent linear response to insolation forcing at obliquity frequencies driven mainly by high-latitude processes. Although the lengths of the time series are short (420 ka) for detecting 100 kyr eccentricity cycles, the phase relationships support those obtained by Shackleton []. Antarctic temperature and the Iberian Margin alcohol ratios (C26OH/(C26OH + C29)) lead eccentricity maxima by 6 kyr, with lower ratios (increased oxygenation) occurring at eccentricity maxima. CO2, CH4, and Iberian SST are nearly in phase with eccentricity, and minimum ice volume (as inferred from Pacific δ18Oseawater) lags eccentricity maxima by 10 kyr. The phase relationships derived in this study continue to support a potential role of the Earth's carbon cycle in contributing to the 100 kyr cycle. |
format |
Article in Journal/Newspaper |
author |
Hodell, David Crowhurst, Simon Skinner, Luke Tzedakis, Polychronis C. Margari, Vasiliki Channell, James E.T. Kamenov, George Maclachlan, Suzanne Rothwell, Guy |
spellingShingle |
Hodell, David Crowhurst, Simon Skinner, Luke Tzedakis, Polychronis C. Margari, Vasiliki Channell, James E.T. Kamenov, George Maclachlan, Suzanne Rothwell, Guy Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka |
author_facet |
Hodell, David Crowhurst, Simon Skinner, Luke Tzedakis, Polychronis C. Margari, Vasiliki Channell, James E.T. Kamenov, George Maclachlan, Suzanne Rothwell, Guy |
author_sort |
Hodell, David |
title |
Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka |
title_short |
Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka |
title_full |
Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka |
title_fullStr |
Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka |
title_full_unstemmed |
Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka |
title_sort |
response of iberian margin sediments to orbital and suborbital forcing over the past 420 ka |
publishDate |
2013 |
url |
http://nora.nerc.ac.uk/id/eprint/502220/ https://nora.nerc.ac.uk/id/eprint/502220/1/palo20017_Hodell.pdf https://doi.org/10.1002/palo.20017 |
geographic |
Antarctic Shackleton Pacific |
geographic_facet |
Antarctic Shackleton Pacific |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
https://nora.nerc.ac.uk/id/eprint/502220/1/palo20017_Hodell.pdf Hodell, David; Crowhurst, Simon; Skinner, Luke; Tzedakis, Polychronis C.; Margari, Vasiliki; Channell, James E.T.; Kamenov, George; Maclachlan, Suzanne; Rothwell, Guy. 2013 Response of Iberian Margin sediments to orbital and suborbital forcing over the past 420 ka. Paleoceanography, 28 (1). 185-199. https://doi.org/10.1002/palo.20017 <https://doi.org/10.1002/palo.20017> |
op_doi |
https://doi.org/10.1002/palo.20017 |
container_title |
Paleoceanography |
container_volume |
28 |
container_issue |
1 |
container_start_page |
185 |
op_container_end_page |
199 |
_version_ |
1766248649146236928 |