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

Origin of delta C-13 minimum events in thermocline and intermediate waters of the western South Atlantic

Full text
Show less -
Nascimento, R. A. [1] ; Santos, T. P. [1] ; Venancio, I. M. [2, 1] ; Chiessi, C. M. [3] ; Ballalai, J. M. [1] ; Kuhnert, H. [4] ; Govin, A. [5] ; Portilho-Ramos, R. C. [4] ; Lessa, D. [1] ; Dias, B. B. [3, 1] ; Pinho, T. M. L. [6] ; Crivellari, S. [3] ; Mulitza, S. [4] ; Albuquerque, A. L. S. [1]
Total Authors: 14
[1] Univ Fed Fluminense, Programa Geociencias Geoquim, Niteroi, RJ - Brazil
[2] Natl Inst Space Res INPE, Ctr Weather Forecasting & Climate Studies CPTEC, Cachoeira Paulista - Brazil
[3] Univ Sao Paulo, Sch Arts Sci & Humanities, Sao Paulo - Brazil
[4] Univ Bremen, MARUM Ctr Marine Environm Sci, Bremen - Germany
[5] Univ Paris Saclay, Lab Sci Climat & Environm, Inst Pierre Simon Laplace, CEA CNRS UVSQ, Gif Sur Yvette - France
[6] Univ Sao Paulo, Inst Geosci, Sao Paulo - Brazil
Total Affiliations: 6
Document type: Journal article
Source: QUATERNARY SCIENCE REVIEWS; v. 272, NOV 15 2021.
Web of Science Citations: 0

Stable carbon isotopic (delta C-13) minimum events have been widely described in marine archives recording the properties of thermocline and intermediate waters during glacial terminations. However, the mechanisms associated with these events remain ambiguous. Here we present three high temporal resolution deep-dwelling planktonic foraminifera delta C-13 records from the main thermocline and one benthic delta C-13 record from the modern core of Antarctic Intermediate Water (AAIW). Our sediment cores are distributed along the western South Atlantic from the equator to the subtropics, with the longest record spanning the last similar to 300 kyr. The results show that delta C-13 minimum events were pervasive features of the last three glacial terminations and Marine Isotope Stage 4/3 transition in the western South Atlantic. Two distinct mechanisms were responsible for the delta C-13 minima at the thermocline and intermediate depths of the Atlantic, respectively. We suggest that the delta C-13 minimum events at the thermocline were mostly driven by the thermodynamic ocean-atmosphere isotopic equilibration, which is supported by calculated delta C-13 of dissolved inorganic carbon in the subtropical western South Atlantic as well as by previously published model simulations. On the other hand, intermediate depths delta C-13 minimum events in the tropics were likely caused by the slowdown of the Atlantic meridional overturning circulation and the associated accumulation of isotopically light carbon at mid and intermediate depths of the Atlantic Ocean. (C) 2021 Elsevier Ltd. All rights reserved. (AU)

FAPESP's process: 18/15123-4 - Past perspectives on tipping elements of the climate system: the Amazon Rainforest and the Atlantic Meridional Overturning Circulation (PPTEAM)
Grantee:Cristiano Mazur Chiessi
Support Opportunities: Research Grants - Research Program on Global Climate Change - Young Investigators - Phase 2
FAPESP's process: 19/24349-9 - Assessing the effects of past and future climate change on Amazonian biodiversity (CLAMBIO)
Grantee:Cristiano Mazur Chiessi
Support Opportunities: BIOTA-FAPESP Program - Regular Research Grants
FAPESP's process: 19/10642-6 - Response of the upper water column at the origin of the Brazil Current to slowdown events of the Atlantic Meridional Ocean Circulation during the last 80 ka
Grantee:Tainã Marcos Lima Pinho
Support Opportunities: Scholarships in Brazil - Master
FAPESP's process: 20/11452-3 - Carbon storage changes in the mid-depth South Atlantic during the penultimate glacial termination and the Anthropocene
Grantee:Bruna Borba Dias
Support Opportunities: Scholarships in Brazil - Post-Doctorate