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@Article{BallalaiSLVCJKTCL:2019:TrSpAg,
               author = "Ballalai, Jo{\~a}o and Santos, Thiago Pereira dos and Lessa, 
                         Douglas Villela de Oliveira and Venancio, Igor Martins and 
                         Chiessi, Cristiano M. and Johnstone, Heather H. and Kuhnert, 
                         Henning and Toledo, Felipe Antonio de Lima and Costa, Karen B. and 
                         Luiza, Albuquerque Ana",
          affiliation = "{Universidade Federal Fluminense (UFF)} and {Universidade Federal 
                         Fluminense (UFF)} and {Universidade Federal Fluminense (UFF)} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade de S{\~a}o Paulo (USP)} and {University of Bremen} 
                         and {University of Bremen} and {Universidade de S{\~a}o Paulo 
                         (USP)} and {Universidade de S{\~a}o Paulo (USP)} and 
                         {Universidade Federal Fluminense (UFF)}",
                title = "Tracking the spread of Agulhas Leakage to the western South 
                         Atlantic and its northward transmission during the last 
                         interglacial",
              journal = "Paleoceanography and Paleoclimatology",
                 year = "2019",
               volume = "34",
               number = "11",
                pages = "1744--1760",
                month = "Nov.",
             keywords = "Termination II, Brazil Current, Agulhas rings, Subtropical gyre, 
                         Atlantic Meridional Overturning Circulation.",
             abstract = "Intensifications of the Agulhas Leakage (AL) during glacial 
                         Terminations have long been proposed as a necessary mechanism to 
                         return the Atlantic Meridional Overturning Circulation (AMOC) to 
                         its interglacial mode. However, the lack of records showing the 
                         downstream evolution of the AL signal and the large temporal 
                         differences between AL intensification and the resumption of 
                         deep-water convection cast doubt on the importance of this 
                         mechanism to the overturning. Here, we analyze a combination of 
                         new and previously published data related to Mg/Ca-derived 
                         temperatures and ice-volume-corrected seawater \δ18O 
                         (\δ18OIVC-SW as a proxy for ocean salinity) that demonstrate 
                         the propagation of the AL signal via surface and thermocline 
                         waters to the western South Atlantic (Santos Basin) during glacial 
                         Termination II and the early Last Interglacial. The saline AL 
                         waters were temporarily stored in the upper subtropical South 
                         Atlantic until two abrupt freshening steps indicate their release 
                         into the North Atlantic via the surface and thermocline waters at 
                         ca. 129 and 123 ka BP, respectively. Considering age 
                         uncertainties, these two steps are coeval with the resumption of 
                         convection in the Labrador and Nordic Seas during the Last 
                         Interglacial. We propose a mechanism in which both a strong AL and 
                         a favorable ocean-atmosphere configuration in the tropical 
                         Atlantic were required to allow the flux of AL waters into the 
                         North Atlantic, where they then contributed to pushing the AMOC 
                         during the Last Interglacial. Our results provide a framework that 
                         connects AL strengthening to the AMOC intensifications that follow 
                         glaciations.",
                  doi = "10.1029/2019PA003653",
                  url = "http://dx.doi.org/10.1029/2019PA003653",
                 issn = "2572-4517",
             language = "en",
           targetfile = "ballalai_tracking.pdf",
        urlaccessdate = "28 mar. 2024"
}


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