Southern Ocean and East Antarctic Temperature Evolution during the Middle Miocene

Abstract

Much of Antarctica was ice-free during the Miocene Climatic Optimum (MCO, ~16.9 to 14.8 Ma), the warmest interval of the Neogene. During the subsequent Middle Miocene Climate Transition (MMCT, ~14.8 to 12.8 Ma), Antarctica reglaciated as global temperatures cooled. Despite spanning this critical threshold for Antarctic glaciation, few published paleotemperature records from Antarctica or the polar Southern Ocean cover the Middle Miocene, and low temporal resolution hinders interpretation of the few existing records. Here, I propose creating orbital-resolution, organic geochemical records from ODP Site 1165 in the polar Southern Ocean to quantify the evolution of ocean and continental surface temperatures during this climatic transition. These proxy records will determine the magnitude of cooling in the polar Southern Ocean and East Antarctica, and their resolution will allow for quantification of orbital-scale temperature variability. These biomarker records will provide the first direct, high-resolution insight into polar temperatures during the Miocene transition from ephemeral to permanent Antarctic glaciation, with implications for the sensitivity of modern ice volume under warmer climate conditions.

Biography

I grew up in Springfield, Virginia, where I became fascinated by the ocean during family trips to the beach. While attending Thomas Jefferson High School for Science and Technology, I discovered my passion for oceanography and geochemistry through participating in the National Ocean Sciences Bowl and aquatic chemistry research. I pursued these interests as an undergraduate at Rice University through obtaining dual degrees in Earth Science and Chemistry. While there, I was introduced to research in paleoceanography through working with Dr. Jeanine Ash to characterize bulk organic matter in Pliocene sediments from the Ross Sea recovered during IODP Expedition 374. These experiences inspired me to pursue a PhD at Brown University working with Prof. Timothy Herbert. I analyze biomarkers in marine sediments to reconstruct high-latitude temperatures during the Middle Miocene, a potential past analogue for future climate. I am excited to use the Schlanger Fellowship to discover how Southern Ocean and East Antarctic temperatures related to dramatic changes in Antarctic ice sheets during this past warm climate, motivated by wanting to understand the long-term consequences of anthropogenic warming on global ice volume and sea level.