USAP-DC

The goals of this collaborative project are to merge empirical observations from the deglaciated Antarctic continental shelf and 1-D and 3-D numerical model experiments to test the sensitivity of marine-based ice sheets to subglacial topography with collaborators at the University of Kansas (L. Stearns, C. van der Veen). We focus on five glacial systems (i.e., flowlines) across the Amundsen Sea, Ross Sea, and George V Coast of Wilkes Land that extended to/near the continental shelf break at the Last Glacial Maximum – with a range of bed characteristics, topographic features, oceanographic and climatic conditions, and patterns of past ice flow and grounding line retreat. Specifically, at the University of Virginia, we (L. Simkins, S. Munevar Garcia) are: (ongoing) exploring bed roughness across the flowlines to determine the sensitivity of ice flow and grounding line behavior to different scales and wavelengths of bed topography/roughness; (upcoming) developing an empirical relationship between ice-marginal landform sediment volume and grounding line occupation time, and combining this with sedimentological analyses and new absolute age constraints to produce more comprehensive timelines of grounding line retreat, influential boundary conditions and processes, and determine the presence/absence of ice shelves; (ongoing) integrating quantitative and qualitative paleo- and offshore data to be incorporated into and/or validate 1-D and 3-D model experiments further testing the sensitivity of the five glacial systems to bed topography; and (completed) co-developing community engagement and education materials that focus on merging paleo-observations and model information of the Antarctic Ice Sheet from the LGM to the present

Person	Role
Simkins, Lauren	Investigator and contact
Stearns, Leigh	Investigator
Anderson, John	Co-Investigator
van der Veen, Cornelis	Co-Investigator

Antarctic Earth Sciences	Award # 1745055
Antarctic Glaciology	Award # 1745055
Antarctic Earth Sciences	Award # 1745043
Antarctic Glaciology	Award # 1745043

USAP-1745043_1

Data_Management.docx

Repository	Title (link)	Format(s)	Status
USAP-DC	Pennell Trough, Ross Sea bathymetry and glacial landforms	GeoTIFF; Excel	exists
USAP-DC	Circum-Antarctic grounding-line sinuosity	GeoTIFF; Excel	exists
USAP-DC	Elevation transects from Pine Island Bay	ZIP Archive	exists

1. Simkins, L. M., Greenwood, S. L., Munevar Garcia, S., Eareckson, E. A., Anderson, J. B., & Prothro, L. O. (2021). Topographic Controls on Channelized Meltwater in the Subglacial Environment. Geophysical Research Letters, 48(20). (doi:10.1029/2021gl094678)
2. Simkins, L. M., Stearns, L. A., & Riverman, K. L. (2021). Controls on circum-Antarctic grounding-line sinuosity. (doi:10.1002/essoar.10509090.1)
3. Munevar Garcia, S., Miller, L. E., Falcini, F. A. M., & Stearns, L. A. (2023). Characterizing bed roughness on the Antarctic continental margin. Journal of Glaciology, 1–12. (doi:10.1017/jog.2023.88)