Earth and Planetary Science Letters 463 (2017) 1–12 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Prolonged warming of the Brazil Current precedes deglaciations Thiago P. Santos a , Douglas O. Lessa a , Igor M. Venancio b , Cristiano M. Chiessi c , Stefan Mulitza b , Henning Kuhnert b , Aline Govin d , Thiago Machado a , Karen B. Costa e , Felipe Toledo e , Bruna B. Dias a , Ana Luiza S. Albuquerque a,∗ a Departamento de Geoquímica, Universidade Federal Fluminense, Niterói, Brazil b MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany c Escola de Artes, Ciências e Humanidades, Universidade de São Paulo, São Paulo, Brazil d Institut Pierre-Simon Laplace/Laboratoire des Sciences du Climat et de l’Environnement, CEA-CNRS-UVSQ, Université Paris Saclay, Gif-sur-Yvette, France e Laboratório de Paleoceanografia do Atlântico Sul, Instituto Oceanográfico, Universidade de São Paulo, Brazil a r t i c l e i n f o a b s t r a c t Article history: Received 2 July 2016 Received in revised form 6 January 2017 Accepted 15 January 2017 Available online xxxx Editor: M. Frank Keywords: South Atlantic early warming South Atlantic glacial–interglacial transition South Atlantic subtropical gyre low-latitude heat and salt accumulation interhemispheric heat transfer Paleoceanographic reconstructions from the Brazil Current are scarce and lack the required temporal resolution to appropriately represent its variability during key periods of the last glacial–interglacial cycles. Here, we present the first high-temporal resolution multiproxy reconstruction of the Brazil Current at 24 ◦ S covering the last 185 ka. During the last and penultimate glacial periods, our Mg/Ca-derived sea surface temperature (SST) record shows a strong cooling at ca. 47 and ca. 156 ka, respectively, that is followed by a warming trend from late-Marine Isotope Stage (MIS) 3 to MIS 1 and from late-MIS 6 to MIS5e, respectively. Importantly, the Brazil Current warmed uninterruptedly towards Termination I (II) after the low SST at ca. 47 and ca. 156 ka, with no SST minima during the Last Glacial Maximum or penultimate glacial maximum. The reason for the strong cooling and the warming trend during late- MIS 3 and late-MIS 6 could reside in the favorable obliquity configuration. However, this mechanism is not sufficient to sustain the warming observed for the rest of the last and penultimate glacial periods. We propose that the change in the Atlantic meridional overturning circulation (AMOC), as described in the literature, from a “warm” to a “cold mode” for MIS 2 and MIS 6 is responsible for the accumulation of warm waters in the subtropical western South Atlantic, preventing SST minima during the last and penultimate glacial maxima in the region. Change in benthic δ 13 C corroborates that a fundamental modification in the AMOC mode might have triggered the heat accumulation. Our data also show a sudden increase in SST and surface salinity during the last glacial descent (MIS 4), indicating that the western portion of the subtropical gyres may have acted as a heat and salt reservoir, while higher latitude climates transited to a glacial background. Our findings imply that the AMOC “cold mode” induces heat storage in the subtropical western South Atlantic and, because of that, the last two regional SST minima occurred out-of-phase with the glacial maxima of higher latitudes.  2017 Elsevier B.V. All rights reserved. 1. Introduction The ultimate pacing of glacial–interglacial variations is linked to cyclic changes in the Earth’s orbital parameters, but orbital varia- tions are insufficient to drive the large amplitude of climatic cycles (Sigman and Boyle, 2000). Internal feedback mechanisms such as atmospheric CO 2 concentrations, the growth and decay of conti- nental ice sheets and the meridional circulation must amplify the climate response to orbital forcing. In order to better explain the role of each internal mechanism it is fundamental to determine * Corresponding author. E-mail address: ana_albuquerque@id.uff.br (A.L.S. Albuquerque). the timing when the distinct natural archives initiated their tran- sition to a subsequent climate pattern. For the South Atlantic and Southern Ocean, available time series indicate that their altered sea surface temperature (SST) precedes North Atlantic SST warm- ing and ice-volume decay at all orbital frequencies by thousands of years (Mulitza et al., 2007). However, the underlying mechanisms for this remain poorly understood, mainly in southern subtropical gyres. Paleoceanographic studies in subtropical regions, therefore, are crucial to accurately determine the causes of this early re- sponse and its possible consequences, since low-latitude oceans provide heat and moisture to high latitudes. In the South Atlantic subtropical gyre, the western branch is dominated by the Brazil Current (BC). Millennial-scale paleoceano- http://dx.doi.org/10.1016/j.epsl.2017.01.014 0012-821X/ 2017 Elsevier B.V. All rights reserved.