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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Variability of the Brazil Current during the late Holocene

Texto completo
Autor(es):
Chiessi, Cristiano M. [1] ; Mulitza, Stefan [2] ; Groeneveld, Jeroen [2] ; Silva, Juliana B. [3] ; Campos, Marilia C. [1] ; Gurgel, Marcio H. C. [1]
Número total de Autores: 6
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Sch Arts Sci & Humanities, Sao Paulo - Brazil
[2] Univ Bremen, MARUM Ctr Marine Environm Sci, D-28359 Bremen - Germany
[3] Univ Sao Paulo, Inst Geosci, Sao Paulo - Brazil
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY; v. 415, n. SI, p. 28-36, DEC 1 2014.
Citações Web of Science: 9
Resumo

Our understanding of the centennial-scale variability of the Brazil Current (BC) during the late Holocene is elusive because of the lack of appropriate records. Here we used the Mg/Ca and oxygen isotopic composition of planktonic foraminifera from two marine sediment cores collected at 27 S and 33 degrees S off southeastern South America to assess the late Holocene variability in the upper water column of the BC. Our results show in phase fluctuations of up to 3 degrees C in sea surface temperatures (SST), and 0.8% in oxygen isotopic composition of surface sea water, a proxy for relative sea surface salinity (SSS). Time-series analyses of our records indicate a cyc.licity with a period of ca. 730 yr. We suggest that the observed cyclicity reflects variability in the strength of the BC associated to changes in the Atlantic meridional overturning circulation (AMOC). Positive (negative) SST and SSS anomalies are related to a strong (weak) BC and a weak (strong) AMOC. Moreover, periods of peak strength in the BC occur synchronously to a weak North Brazil Current, negative SST anomalies in the high latitudes of the North Atlantic, and positive (negative) precipitation anomalies over southeastern South America (equatorial Africa), further corroborating our hypothesis. This study shows a tight coupling between the variability of the BC and the high latitudes of the North Atlantic mediated by the AMOC even under late Holocene boundary conditions. (C) 2013 Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 10/09983-9 - Mudanças na temperatura da superfície do mar no Oeste do Atlântico Sul e variabilidade na precipitação no Sudeste da América do Sul desde o Último Máximo Glacial
Beneficiário:Cristiano Mazur Chiessi
Linha de fomento: Auxílio à Pesquisa - Regular
Processo FAPESP: 12/17517-3 - Resposta da porção oeste do Oceano Atlântico às mudanças na circulação meridional do Atlântico: variabilidade milenar a sazonal
Beneficiário:Cristiano Mazur Chiessi
Linha de fomento: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Jovens Pesquisadores