Variability of the Brazil Current and South American climate during the last glacial cycle: assessing sea-surface temperatures via Mg/Ca analyses and pulses of terrigenous sediments via X-ray fluorescence analyses

• Grant number: 18/06790-7
• Support type: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): July 09, 2018
• Effective date (End): January 03, 2019
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal researcher: Cristiano Mazur Chiessi
• Grantee: Marília de Carvalho Campos Garcia
• Supervisor abroad: Stefan Mulitza
• Home Institution: Escola de Artes, Ciências e Humanidades (EACH). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: University of Bremen, Germany
• Associated to the scholarship: 16/10242-0 - Occurrence and impact of the mega-South Atlantic Convergence Zone over the eastern South America during the last glacial period: a paleoceanographic approach, BP.DR

Abstract

The western boundary currents of the South Atlantic play a fundamental role in the distribution of energy between the hemispheres. The Brazil Current (BC), for instance, stores and redirects towards the mean latitudes of the Southern Hemisphere a significant portion of heat during periods of a weak Atlantic Meridional Overturning Circulation. Additionally, the BC influences the South Atlantic Converge Zone (SACZ), which is responsible for summer precipitation in a large sector of South America. The SACZ is also a crucial source of precipitation to the São Francisco River drainage basin, the largest drainage basin in eastern South America (ESA), whose response to millennial-scale climate events is poorly known. The data so far obtained under the PhD project of the candidate are very promising and will most probably provide a significant improvement on our understanding of millennial-scale changes in the BC and in the climate of ESA. The requested research internship aims at reconstructing (i) the variability in sea-surface temperatures of the BC, and (ii) changes in precipitation over the São Francisco River drainage basin through pulses of terrigenous sediments around 10.5°S for the last glacial cycle based on Mg/Ca analyses in planktonic foraminiferal tests and X-ray fluorescence analyses in bulk sediment samples, respectively. Therefore, we will investigate marine sediment cores M125-95-2/3 collected at a site under the influence of the BC and subject to the delivery of terrigenous sediments from the São Francisco River drainage basin.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHIESSI, C. M.; MULITZA, S.; TANIGUCHI, N. K.; PRANGE, M.; CAMPOS, M. C.; HAEGGI, C.; SCHEFUSS, E.; PINHO, T. M. L.; FREDERICHS, T.; PORTILHO-RAMOS, R. C.; SOUSA, S. H. M.; CRIVELLARI, S.; CRUZ, F. W. Mid- to Late Holocene Contraction of the Intertropical Convergence Zone Over Northeastern South America. PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY, v. 36, n. 4 APR 2021. Web of Science Citations: 0.

CAMPOS, MARILIA C.; CHIESSI, CRISTIANO M.; VENANCIO, IGOR M.; PINHO, TAINA M. L.; CRIVELLARI, STEFANO; KUHNERT, HENNING; SCHMIEDL, GERHARD; DIAZ, RUT A.; ALBUQUERQUE, ANA LUIZA S.; PORTILHO-RAMOS, RODRIGO C.; BAHR, ANDRE; MULITZA, STEFAN. Constraining Millennial-Scale Changes in Northern Component Water Ventilation in the Western Tropical South Atlantic. PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY, v. 35, n. 7 JUL 2020. Web of Science Citations: 0.

CAMPOS, MARILIA C.; CHIESSI, CRISTIANO M.; PRANGE, MATTHIAS; MULITZA, STEFAN; KUHNERT, HENNING; PAUL, ANDRE; VENANCIO, IGOR M.; ALBUQUERQUE, ANA LUIZA S.; CRUZ, FRANCISCO W.; BAHR, ANDRE. A new mechanism for millennial scale positive precipitation anomalies over tropical South America. QUATERNARY SCIENCE REVIEWS, v. 225, DEC 1 2019. Web of Science Citations: 0.