Dynamics of the Malvinas Current and Brazil-Malvinas Confluence in the southwestern South Atlantic since the late Quaternary

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The Brazil-Malvinas Confluence (BMC), is a highly energetic convergence of surface currents in the southwestern South Atlantic, formed near the latitude of 38°S. The BMC has been shifted southwards in the last decades, is projected to continue in the future. The BMC act as a natural barrier and plays an important role in controlling the heat transfer from the tropical South Atlantic to the Southern Ocean. Thus, the projected southward shift of the BMC can cause various impacts on the global ocean currents circulation and global climate. The southward shift of the BMC can also cause issues such as warming up the air temperature by releasing additional heat from the tropical waters that will lead to the melting of the ice sheet in the Antarctic and indirectly rising of the global sea-level. So far, most of the studies are restricted on the Brazil Current (BC), the northern branch of the BMC. However, studies on the long-term changes of the Malvinas Current (MC) and its influence of the southern branch of the BMC is still missing. Thus, a transect of marine sediment cores from the southern branch of the MC and BMC itself are planned to be studied. Marine palynological studies are powerful tools to investigate past marine and continental environment changes. Multi-proxy analyses, including pollen, spores, organic- and calcareous-walled dinoflagellate cysts and freshwater algae in marine sediment cores will be applied. By analysing the palynological records, the stability and past dynamics of the MC and BMC will be reconstructed since the LGM. Moreover, the regional latitudinal shifts of the BMC and its impact on local marine as well as adjacent continental environment and climate will be investigated and modelled as well. This study also aims to investigate past driving mechanisms for controlling the latitude shifts of BMC, and shed light for the prediction and modeling of future scenarios to the recent poleward migrations of the BMC under global warming.