Subantarctic Pacific biomarker-based upper ocean temperature and Patagonian Ice Sheet dynamics during the past 160,000 years

• Main Author: Hagemann, Julia
• Other Authors: Tiedemann, Ralf, Pahnke, Katharina
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Universität Bremen 2023
• Subjects: Biomarker; Patagonian ice sheet; last interglacial (MIS 5); ACC; South Pacific Ocean; sea surface temperature; 550; 550 Earth sciences and geology; ddc:550; Pacific; Ice Sheet
• Online Access: https://media.suub.uni-bremen.de/handle/elib/6976; https://doi.org/10.26092/elib/2297; https://nbn-resolving.org/urn:nbn:de:gbv:46-elib69767

A fundamental understanding of the climatic system is necessary to estimate future global warming risks and consequences better. Clues and information about the interaction of individual components in the climate system can be found in our recent geological past, in which warmer and cooler periods have alternated. In this thesis, alkenone and Glycerol Dialkyl Glycerol Tetraether (GDGT) – based water temperatures were reconstructed to document changes in the physical structure of the South Pacific. Furthermore, terrestrial-produced n-alkanes and branched (br)GDGTs were also determined for site MR16-09 PC03 at the Chilean margin to document the interaction between the nearby Patagonian Ice Sheet (PIS) and the ocean. These topics were addressed in three main chapters for peer-reviewed international scientific journals. A first study was about the applicability of alkenone and GDGT-derived temperatures in the South Pacific. A second study used South Pacific sea surface and subsurface temperatures to determine changes in the physical structure of the upper ocean during the transition of the Penultimate glacial to the Last Interglacial maximum. A third study addresses continent-ocean interaction over a complete glacial/interglacial cycle at the Chilean continental margin using alkenones and terrestrial biomarkers.