Skip navigation
Skip navigation

Heat export from the tropics drives mid to late Holocene palaeoceanographic changes offshore southern Australia

Perner, Kerstin; Moros, Matthias; De Deckker, Patrick; Blanz, Thomas; Wacker, Lukas; Telford, Richard J.; Siegel, Herbert; Schneider, Ralph; Jansen, Eystein

Description

The Leeuwin Current (LC), an eastern boundary current, transports tropical waters from the Indo-Pacific Warm Pool (IPWP) towards southern latitudes and modulates oceanic conditions offshore southern Australia. New, high-resolution planktic foraminifer assemblage data and alkenone-derived sea surface temperatures (SST) provide an in-depth view on LC variability and mechanisms driving the current's properties during the mid to late Holocene (last c. 7.4 ka BP). Our marine reconstructions...[Show more]

dc.contributor.authorPerner, Kerstin
dc.contributor.authorMoros, Matthias
dc.contributor.authorDe Deckker, Patrick
dc.contributor.authorBlanz, Thomas
dc.contributor.authorWacker, Lukas
dc.contributor.authorTelford, Richard J.
dc.contributor.authorSiegel, Herbert
dc.contributor.authorSchneider, Ralph
dc.contributor.authorJansen, Eystein
dc.date.accessioned2021-05-12T01:35:17Z
dc.identifier.issn0277-3791
dc.identifier.urihttp://hdl.handle.net/1885/232672
dc.description.abstractThe Leeuwin Current (LC), an eastern boundary current, transports tropical waters from the Indo-Pacific Warm Pool (IPWP) towards southern latitudes and modulates oceanic conditions offshore southern Australia. New, high-resolution planktic foraminifer assemblage data and alkenone-derived sea surface temperatures (SST) provide an in-depth view on LC variability and mechanisms driving the current's properties during the mid to late Holocene (last c. 7.4 ka BP). Our marine reconstructions highlight a longer-term mid to late Holocene reduction of tropical heat export from the IPWP area into the LC. Mid Holocene (c. 7.4 to 3.5 ka BP) occurrence of high SSTs (>19.5 °C), tropical planktic foraminifera and a well-stratified water column document an enhanced heat export from the tropics. From c. 3.5 ka BP onwards, a weaker LC and a notably reduced tropical heat export cause oceanic cooling offshore southern Australia. The observed mid to late Holocene trends likely result from large-scale changes in the IPWP's heat storage linked to the El Niño-Southern Oscillation (ENSO) phenomenon. We propose that a strong and warm LC occurs in response to a La Niña-like state of ENSO during the mid Holocene. The late Holocene LC cooling, however, results from a shift towards an El Niño-like state and a more variable ENSO system that causes cooling of the IPWP. Superimposed on these longer-term trends we find evidence of distinct late Holocene millennial-scale phases of enhanced El Niño/La Niña development, which appear synchronous with northern hemispheric climatic variability. Phases of dominant El Niño-like states occur parallel to North Atlantic cold phases: the ‘2800 years BP cooling event’, the ‘Dark Ages’ and the ‘Little Ice Age’, whereas the ‘Roman Warm Period’ and the ‘Medieval Climate Anomaly’ parallel periods of a predominant La Niña-like state. Our findings provide further evidence of coherent interhemispheric climatic and oceanic conditions during the mid to late Holocene, suggesting ENSO as a potential mediator.
dc.description.sponsorshipThis study was supported by AINSE grant 05/036 awarded to PDD and an ARC grant (DP0344932) contributed towards the costs to obtain the cores and their processing.
dc.format.mimetypeapplication/pdf
dc.language.isoen_AU
dc.publisherPergamon-Elsevier Ltd
dc.rights© 2017 Elsevier Ltd.
dc.sourceQuaternary Science Reviews
dc.subjectPlanktic foraminifer
dc.subjectSea surface temperature
dc.subjectPalaeoceanography
dc.subjectENSO
dc.subjectHolocene
dc.subjectSouthern Ocean
dc.subjectAustralia
dc.titleHeat export from the tropics drives mid to late Holocene palaeoceanographic changes offshore southern Australia
dc.typeJournal article
local.description.notesImported from ARIES
local.identifier.citationvolume180
dcterms.dateAccepted2017-11-22
dc.date.issued2018-01-15
local.identifier.absfor040503 - Physical Oceanography
local.identifier.absfor210303 - Australian History (excl. Aboriginal and Torres Strait Islander History)
local.identifier.ariespublicationa383154xPUB8834
local.publisher.urlhttps://www.sciencedirect.com/
local.type.statusPublished Version
local.contributor.affiliationPerner, Kerstin, Leibniz Institute for Baltic Sea Research
local.contributor.affiliationMoros, Matthias, Leibniz Institute for Baltic Sea Research
local.contributor.affiliationDe Deckker, Patrick, College of Science, ANU
local.contributor.affiliationBlanz, Thomas, Laboratory of Ion Beam Physics
local.contributor.affiliationWacker, Lukas, Kiel University
local.contributor.affiliationTelford, Richard J., University of Bergen
local.contributor.affiliationSiegel, Herbert, Leibniz Institute for Baltic Sea Research
local.contributor.affiliationSchneider, Ralph, Laboratory of Ion Beam Physics
local.contributor.affiliationJansen, Eystein, University of Bergen
local.description.embargo2099-12-31
dc.relationhttp://purl.org/au-research/grants/arc/DP0344932
local.bibliographicCitation.startpage96
local.bibliographicCitation.lastpage110
local.identifier.doi10.1016/j.quascirev.2017.11.033
dc.date.updated2020-11-23T11:43:06Z
local.identifier.scopusID2-s2.0-85035789379
CollectionsANU Research Publications

Download

File Description SizeFormat Image
01_Perner_Heat_export_from_the_tropics_2018.pdf3.94 MBAdobe PDF    Request a copy


Items in Open Research are protected by copyright, with all rights reserved, unless otherwise indicated.

Updated:  19 May 2020/ Responsible Officer:  University Librarian/ Page Contact:  Library Systems & Web Coordinator