USAP-DC

Hall/1643248 This award supports a project to reconstruct the behavior of a portion of the East Antarctic Ice Sheet (the Ross Ice Sheet), using glacial geologic mapping and radiocarbon dating of algal deposits contained in glacial moraines, at the end of the last glacial period. The results will be compared with other dating methods that will be used on alpine glaciers that terminated in the mountains of the Royal Society Range in East Antarctica during the last glacial maximum and whose landforms intersect with those of the Ross Ice Sheet. Results from this comparison will contribute to a better understanding of the Antarctic ice sheet during the most recent global warming that ended the last ice age. This period is of interest since it will help inform our understanding of Antarctic ice sheet behavior in a future climate warming. Such data also will help inform models that attempt to simulate not only the behavior of the ice sheet during the end of the last ice age, but also its future response to elevated atmospheric carbon dioxide. The work will contribute to the education and training of both graduate and undergraduate students and results from the work will be incorporated in classes at the University of Maine. Results derived from the research will be disseminated to the public through lectures and visits to K-12 classrooms and data from this project will be downloadable from a University of Maine web site, as well as from public data repositories. The Antarctic Ice Sheet exerts a key control on global sea levels, both past and future, and strongly influences Southern Hemisphere and even global climate and ocean circulation. And yet a complete understanding of the evolution of the ice sheet over the last glacial cycle and of the mechanisms that caused it to advance and retreat is still lacking. Of particular interest is the response of the Antarctic Ice Sheet to the global warming that ended the last ice age, because it yields important clues about likely future ice-sheet behavior under a warming climate. In this project, scientists will reconstruct the thinning history of the Antarctic Ice Sheet in the Ross Sea sector during the last glacial/interglacial transition on the headlands of the southern Royal Society Range. They will use a combination of glacial geomorphological mapping and radiocarbon dating of algal deposits enclosed within recessional moraines. Finally, this record will be compared with a beryllium- and radiocarbon-dated chronology that will be produced of adjacent independent alpine glaciers that terminated on land during the last glacial maximum and whose deposits show cross-cutting relationships with those of the ice sheet. Results from this comparison will bear on the behavior of the Antarctic Ice Sheet during the termination of the last ice age. This work will support six students, including at least three undergraduates, and involves field work in the Antarctic.

Person	Role
Hall, Brenda	Investigator and contact
Denton, George	Co-Investigator

Antarctic Earth Sciences	Award # 1643248
Antarctic Glaciology	Award # 1643248

USAP-1643248_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	Marshall Valley U-Series Data	ASCII	exists
USAP-DC	Marshall Valley Radiocarbon Data	ASCII	exists
USAP-DC	Pyramid Trough Radiocarbon Data	Excel	exists
USAP-DC	Walcott Glacier area radiocarbon data	Excel	exists
USAP-DC	Walcott Glacier Exposure Data	Excel	exists

1. Heath, S., Hall, B., Denton, G., Henderson, G., and Hendy, C., 2022. Ice-sheet expansion from the Ross Sea into McMurdo Sound, Antarctica, during the last two glaciations. Quaternary Science Reviews 278, 107379.
2. Miles, M., Hall, B., and Denton, G., 2021. Past interactions between local glaciers and the grounded Ross Sea ice in the Royal Society Range, Antarctica. US-SCAR Meeting, July 2021.
3. Miles, M., Hall, B., and Denton, G., 2020. Asynchronous behavior of local glaciers and grounded Ross Sea ice in the Royal Society Range, Antarctica, during the Last Glacial Maximum and deglaciation. West Antarctic Ice Sheet Annual Meeting.
4. Hall, B., 2020. Behavior of grounded ice in McMurdo Sound during Termination I. West Antarctic Ice Sheet Annual Meeting.
5. Walther, T., Hall, B., and Denton, G., 2019. Reconstruction of Koettlitz Glacier, southern McMurdo Sound, during the last glacial maximum and termination. Geological Society of America Annual Meeting, Phoenix, AZ.
6. Miles, M., Hall, B., and Denton, G., 2019. Relationship between land-terminating Walcott and Howchin Glaciers and adjacent marine-grounded Ross Sea ice in the Royal Society Range, Antarctica. Interdisciplinary Antarctic Earth Sciences Meeting, Julian, CA.
7. Hall, B., Denton, G., Heath, S., Henderson, G., Jackson, M., Koffman, T., Mattas, L., Miles, M., and Walther, T., 2019. Extent and age of Ross Sea drifts during the last two glaciations, McMurdo Sound, Antarctica. Interdisciplinary Antarctic Earth Sciences Meeting, Julian, CA.
8. Walther, T., Hall, B., and Denton, G., 2019. Reconstruction of Koettlitz Glacier in the McMurdo Sound Region, Antarctica during the last glacial maximum and termination. NE Geological Society of America, Portland, Maine.
9. Miles, M., Hall, B., and Denton, G., 2019. Reconstructing the behavior of the land-terminating Walcott Glacier since the Last Glacial Maximum in the Royal Society Range, Antarctica. NE Geological Society of America, Portland, Maine.