Onset and modifications in intensity and pathways of water mass exchange between the Southeast Pacific and the South Atlantic with focus on the Falkland Plateau

• Main Author: Uenzelmann-Neben, Gabriele
• Format: Conference Object
• Language: unknown
• Published: 2019
• Subjects: Antarctic; Drake Passage; Falkland Plateau; Pacific; Scotia Sea; The Antarctic; Weddell; Weddell Sea; Antarc*; Antarctica
• Online Access: https://epic.awi.de/id/eprint/49383/; https://hdl.handle.net/10013/epic.d291563d-c4f6-411c-9095-16c951d01678

The opening of Drake Passage and the Scotia Sea enabled the exchange of water masses between the southern Pacific and the South Atlantic. In this way heat and energy could be transferred between the two oceans. Together with the opening of the Tasman Gateway this allowed the establishment of the Antarctic Circumpolar Current (ACC) thermally isolating Antarctica, which has been considered as one of the major causes for the onset of widespread glaciation. Both tectonic movements within Drake Passage and the Scotia Sea as well as modifications in climate have led to changes in intensity and pathway of the ACC and the water masses flowing within it. The onset of the ACC and those changes have been documented in sedimentary structures deposited on the Falkland Plateau. A study of the sediment drifts shaped by Circumpolar Deepwater, Weddell Sea Deepwater and Antarctic Bottomwater will provide information on modifications of the circulation resulting from tectonic movements and changes in climate. A grid of high-resolution seismic data collected during expedition MSM 81 with RV Maria S Merian will allow the deciphering of the sediment drifts structures as well as their modification and reshaping and the identification and relocation of depot centres. Additionally, the data will form the base for a site survey package for IODP proposal 862 set on studying the earliest phase of water mass exchange via Drake Passage.