C051-01
Hercules Dome ice core project: Prospects for obtaining Eemian records that constrain the size of the West Antarctic ice sheet through time.
Monday, 14 December 2020: 16:00
Virtual
Eric J. Steig1, Marina Duetsch1, Peter N Blossey2, Andrew Pauling3, Cecilia M Bitz3, Murat Aydin4, T. J. Fudge1, Heidi A Roop5, Joseph M Souney Jr6, Mark Twickler6, Knut A Christianson1, John Erich Christian1, Lindsey Davidge1, Benjamin H Hills7, Andrew Osten Hoffman1, Nicholas Holschuh1, Annika Noel Horlings1 and Gemma K. O'Connor1, (1)University of Washington, Earth and Space Sciences, Seattle, WA, United States, (2)University of Washington, Seattle, WA, United States, (3)University of Washington, Atmospheric Sciences, Seattle, WA, United States, (4)University of California Irvine, Irvine, CA, United States, (5)University of Minnesota, Department of Soil, Water, and Climate, Saint Paul, United States, (6)University of New Hampshire, Durham, NH, United States, (7)Applied Physics Laboratory University of Washington, Polar Science Center, Seattle, WA, United States
Abstract:
Hercules Dome, East Antarctica (~86°S, 105°W), is the site of a planned deep-drilling project. Radar surveys in the last two years confirm the original suggestion of Jacobel et al. (2005) that Hercules Dome is a promising location to obtain a long, highly-resolved ice core record. We have identified two possible drilling sites at Hercules Dome that are likely to preserve ice through the last interglacial (Eemian) period, 132 to 115 kyr ago. Ice from the Eemian at Hercules Dome is of particular interest because it may provide a record of changes to the adjacent West Antarctic ice sheet (WAIS) (Steig et al, 2015).
To evaluate the impact of a changing WAIS on the climate at Hercules Dome, simulations were conducted at 15 km resolution over Antarctica using the Weather Research and Forecasting (WRF) model, updated to include water isotopologues, with boundary conditions provided by the Community Earth System Model (iCESM). We find that a lowering or collapse of the WAIS would result in significant changes in temperature, isotope ratios, precipitation, and possibly pressure variability, that should be detectable in a core from the site. Furthermore, changes to the spatial pattern of precipitation would occur that could potentially be detected with highly-resolved radar stratigraphy combined with a well-dated ice core record.
The Hercules Dome ice core drilling is expected to begin in 2023. Community workshops and other information sessions during the intervening years will provide opportunities for broad community involvement and development of collaborative research proposals for scientific work on the core.
Citations:
Jacobel et al., 2005: doi:10.1029/2004JF000188
Steig et al., 2015: doi:10.1002/2015GL063861
