Paleoclimate in the Cenozoic time: Quantifying the role of North Atlantic plate tectonics and mantle processes
Appears in the following Collection
- Institutt for geofag 
AbstractIn the Cenozoic time (66 – 0 Ma) the global climate changed from greenhouse to icehouse conditions. Changes in continents and ocean geometry, geography, and topography due to plate tectonics, erosion, and mantle dynamics played an important role in this complex transition. This thesis explores how the paleobathymetry of Northern Hemisphere oceanic gateways active during Cenozoic influenced the ocean circulation and climate variations. First, this study analyzes the distribution of oceanic sediments and the age of the oceanic lithosphere in the world’s oceans and derives analytical formulas to mathematically describe sedimentation trends in the major oceanic basins. Second, this methodology is implemented in a new global paleogeography model, including detailed reconstructions of the Northern Hemisphere oceanic gateways, ultimately providing a set of realistic global paleogeographic reconstructions for the Cenozoic time. Third, the climatic influence of oceanic gateway geometry at the Eocene-Oligocene Transition (ca. 34 Ma) is modelled using the Norwegian Earth System Model. These simulations show that the climate is highly sensitive to the evolution of the Atlantic – Arctic oceanic gateways.
List of papers
|Paper I (Chapter II): GlobSed: Updated Total Sediment Thickness in the World’s Oceans. E. O. Straume, C. Gaina, S. Medvedev, K. Hochmuth, K. Gohl, J. M. Whittaker, R. Abdul Fattah, J.C. Doornenbal, J. R. Hopper. Published in Geochemistry, Geophysics, Geosystems in March 2019. DOI: 10.1029/2018GC008115. The paper is included in the thesis. Also available in DUO: http://urn.nb.no/URN:NBN:no-79904|
|Paper II (Chapter III): Global Cenozoic Paleobathymetry with a focus on the Northern Hemisphere Oceanic Gateways. E. O. Straume, C. Gaina, S. Medvedev, K. H. Nisancioglu. Published in Gondwana Research in June 2020. DOI: 10.1016/j.gr.2020.05.011. The paper is included in the thesis. Also available at: https://doi.org/10.1016/j.gr.2020.05.011|
|Paper III (Chapter IV): Cooling of the Northern Hemisphere triggered by Northeast Atlantic opening at the Eocene – Oligocene Transition. E. O. Straume, A. Nummelin, C. Gaina, K. H. Nisancioglu. Submitted to PNAS. To be published. The paper is not available in DUO awaiting publishing.|