Holocene climate variability along the coastal margins of Adélie Land, East Antarctica

Johnson, Katelyn

Holocene climate variability along the coastal margins of Adélie Land, East Antarctica

Thursday, 3 December 2020: 17:23

Katelyn Johnson, GNS Science, Lower Hutt, New Zealand, Robert M Mckay, Victoria University of Wgtn, Wellington, New Zealand, Johan Etourneau, Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad Granada, Granada, Spain, Francisco José Javier Jiménez-Espejo, JAMSTEC Japan Agency for Marine-Earth Science and Technology, Kanagawa, Japan, Albot B Anya, Victoria University of Wellington, Wellington, New Zealand, Christina R Riesselman, University of Otago, Departments of Geology and Marine Science, Dunedin, New Zealand, Nancy A.N. Bertler, Victoria University of Wellington and GNS Science, Antarctic Research Centre, Wellington, New Zealand, Huw Joseph Horgan, Victoria University of Wellington, Antarctic Research Centre, Wellington, New Zealand, Xavier Crosta, Université de Bordeaux, Environnements et Paléoenvironnements Océaniques et Continentaux, Bordeaux, France, James A Bendle, University of Birmingham, School of Geography, Earth and Environmental Sciences, Birmingham, United Kingdom, Masako Yamane, Nagoya University, Institute for Space-Earth Environmental Research, Nagoya, Japan, Yusuke Yokoyama, University of Tokyo, Atmosphere and Ocean Research Institute, Bunkyo-ku, Japan, Stephen F Pekar, Queens College, Flushing, NY, United States, Carlota Escutia, University of Granada, Granada, Spain, Robert B Dunbar, Stanford University, Stanford, CA, United States and Kate Ashley, University of Birmingham, Birmingham, United Kingdom

Abstract:

Characterizing the impact of climate oscillations on Antarctica’s coastal margins is difficult due to sparse and temporally limited satellite and observational records. Even more challenging is contextualizing the long-term centennial to decadal variability of the oceanographic, atmospheric, and biological interactions along these margins. Critical components of the climate system, such as sea ice extent, primary productivity, ocean circulation, and bottom water formation may be capable of changing at centennial to decadal timescales, and understanding this change is important for future climate projections. High-resolution paleoclimate reconstructions provide a way to assess these changes and better constrain ice-ocean-atmosphere interactions. Here, we present a near-annually resolved Integrated Ocean Drilling Program (IODP) sediment record, U1357B, from the Adélie Basin, East Antarctica. Throughout the entire 170 m of core, we quantify the continuous, alternating light and dark centimeter-scale laminations, with light laminations interpreted to reflect biogenic bloom events. Using X-Ray Computed Tomography, and supported by XRF data, diatom analysis, grain size analysis, and other physical properties, we developed a record of biogenic bloom events and link them to changing environmental conditions throughout the Holocene. Last, we explore the unique
opportunity and challenges associated with integrating U1357B with the eastern Ross Sea RICE ice core to investigate long-term regional change.