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Titel |
The response of the Peruvian Upwelling Ecosystem to centennial-scale global change during the last two millennia |
VerfasserIn |
R. Salvatteci, D. Gutiérrez, D. Field, A. Sifeddine, L. Ortlieb, I. Bouloubassi, M. Boussafir, H. Boucher, F. Cetin |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1814-9324
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Digitales Dokument |
URL |
Erschienen |
In: Climate of the Past ; 10, no. 2 ; Nr. 10, no. 2 (2014-04-09), S.715-731 |
Datensatznummer |
250116948
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Publikation (Nr.) |
copernicus.org/cp-10-715-2014.pdf |
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Zusammenfassung |
The tropical Pacific ocean–atmosphere system influences global climate on
interannual, decadal, as well as longer timescales. Given the uncertainties
in the response of the tropical Pacific to increasing greenhouse gasses, it
is important to assess the role of the tropical Pacific climate variability
in response to past global changes. The Peruvian Upwelling Ecosystem (PUE)
represents an ideal area to reconstruct past changes in the eastern tropical
Pacific region because productivity and subsurface oxygenation are strongly
linked to changes in the strength of the Walker circulation. Throughout the
last 2000 years, warmer (the Roman Warm Period – RWP; the Medieval Climate
Anomaly – MCA; and the Current Warm Period – CWP), and colder (the Dark
Ages Cold Period – DACP – and Little Ice Age – LIA) intervals were
identified in the Northern Hemisphere (NH). We use a multi-proxy approach
including organic and inorganic proxies in finely laminated sediments
retrieved off Pisco (~14° S), Peru to reconstruct the PUE
response to these climatic periods. Our results indicate that the
centennial-scale changes in precipitation are associated with changes in the
Intertropical Convergence Zone (ITCZ) meridional displacements and
expansion/contraction of the South Pacific Sub-tropical High (SPSH).
Additionally, during the NH cold periods, the PUE exhibited an El
Niño-like mean state, characterized by a weak oxygen minimum zone (OMZ),
and low marine productivity. In contrast, during the RWP, the last stage of
the MCA and the CWP, the PUE exhibited a La Niña-like mean state,
characterized by an intense OMZ and high marine productivity. Comparing our
results with other relevant paleoclimatic reconstructions revealed that
changes in the Walker circulation strength and the SPSH expansion/contraction
controlled marine productivity and OMZ intensity changes during the past two
millennia. |
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