ADDRESSING THE IMPACT OF ICE SHELF RETREAT ON LOCAL CLIMATE: A CASE STUDY OF THE EFFECTS OF THE ROSS ICE SHELF RETREAT ON THE SURROUNDING COASTAL AREA
Sarah Aarons1, Sarah Aciego1, Paolo Gabrielli2, Barbara Delmonte3, Janne Koornneef4, Anna Wegner5, Molly Blakowski1.
1University of Michigan, Ann Arbor, MI, 2Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH, 3University of Milano-Bicocca, Milan, IT, 4Vrije University Amsterdam, Amsterdam, NL, 5Institut fur Polar-und Meeresforschung, Alfred Wegener Institute, Bremerhaven, DE.
Ice cores from Antarctica provide valuable records of past climates encompassing hundreds of thousands of years. Recent declines in ice shelf and sea ice extent in polar regions highlight the importance of evaluating variations in local weather patterns due to climate change. Chemical and mineralogical characterization of airborne mineral particles (dust) transported through the atmosphere and deposited on ice sheets and glaciers in Antarctica allows reconstruction of regional and global climatic systems throughout time. We present the first high-time resolution radiogenic isotope data for Holocene dust in a coastal East Antarctic ice core, accompanied with rare earth element (REE) composition, dust concentration, and size distribution of dust during the Last Glacial Maximum (LGM)-Holocene transition. We use these combined ice core data to determine dust provenance, with variations indicative of shifts in either dust production, sources, and/or transport pathways. A series of 15 samples from the Taylor Dome (77°47'47'' S, 158°43'26'' E) ice core from 1.8 - 31.5 ka were analyzed. The Holocene dust dataset displays a broad range in isotopic and REE composition, suggesting a shift from long-range transported dust to a more variable, local input related to the retreat of the Ross Ice Shelf following the termination of the LGM. Changes in the dust deposited on coastal Antarctic ice can thus be used to infer an evolving local climate, and we extend this study to include the time period of 0 - 55 ka using ice from a horizontal ice core taken from the Taylor Glacier, the outlet glacier for Taylor Dome.