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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

South Brazilian Bight mid- to late Holocene hydrographic fluctuations

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Author(s):
Nagai, Renata H. [1] ; Chiessi, Cristiano M. [2] ; Kuhnert, Henning [3] ; Sousa, Silvia H. M. [4] ; Wainer, Ilana E. K. C. [4] ; Figueira, Rubens C. L. [4] ; Mahiques, Michel M. [4, 5]
Total Authors: 7
Affiliation:
[1] Univ Fed Parana, Ctr Estudos Mar, Ave Beira Mar S-N, BR-83255976 Pontal Do Parana, PR - Brazil
[2] Univ Sao Paulo, Escola Artes Ciencias & Humanidade, Sao Paulo - Brazil
[3] Univ Bremen, MARUM Ctr Marine Environm Sci, Bremen - Germany
[4] Univ Sao Paulo, Inst Oceanog, Sao Paulo - Brazil
[5] Univ Sao Paulo, Inst Energia & Ambiente, Sao Paulo - Brazil
Total Affiliations: 5
Document type: Journal article
Source: GEO-MARINE LETTERS; v. 40, n. 6, SI, p. 1045-1055, DEC 2020.
Web of Science Citations: 0
Abstract

Here, we present two high temporal resolution Holocene sea surface temperature (SST) and salinity (SSS) reconstructions for the SW Atlantic. Mg/Ca data together with the oxygen isotopic composition (delta O-18) of a shallow dwelling planktonic foraminifera species (Globigerinoides ruber(pink)). Two marine sediment cores collected at similar to 25 degrees S are used to assess mid- to late Holocene sea surface hydrographic conditions in the continental shelf of the South Brazilian Bight. Our results show multi-centennial-scale changes of up to 2.7 degrees C in SST and 0.8 parts per thousand in ice volume corrected seawater delta O-18 (a proxy for SSS, indicating changes of up to 2 salinity units). In phase, multicentennial-scale negative SST and SSS incursions were interpreted to indicate shelf-break upwelling events and the northward intrusion of the Plata Plume Water (PPW) under a strengthened Brazil Current (BC) flow. The latitudinal SST gradient between our two records (Delta SST7616-7610), applied here as a proxy for the BC strength, supports the existing hypothesis of antiphase between the BC and the North Brazil Current strength during the last 7 ka. Positive Delta SST(7616-7610)values suggest the presence of the PPW at latitudes of up to 25.5 degrees S, while negative Delta SST(7616-7610)values (centred at around 5.4, 4.3, 2.2 and 1.3 cal ka BP) occurring synchronously with cold events in the Northern Hemisphere suggests that the Atlantic Meridional Overturning Circulation played a central role in the SW Atlantic mid- to late Holocene surface hydrographic conditions. (AU)

FAPESP's process: 12/17517-3 - Response of the Western Atlantic Ocean to changes in the Atlantic meridional overturning circulation: from millennial to seasonal variability
Grantee:Cristiano Mazur Chiessi
Support type: Research Program on Global Climate Change - Young Investigators
FAPESP's process: 09/01594-6 - Productivity changes in the south-southeastern Brazilian continental shelf, during Mid and Late Holocene: a multiproxy approach
Grantee:Renata Hanae Nagai
Support type: Scholarships in Brazil - Doctorate
FAPESP's process: 10/09983-9 - Sea surface temperature changes in the western South Atlantic and precipitation variability in southeastern South America since the Last Glacial Maximum
Grantee:Cristiano Mazur Chiessi
Support type: Regular Research Grants