USAP-DC

This project will investigate the marine component of the Totten Glacier and Moscow University Ice Shelf, East Antarctica. This system is of critical importance because it drains one-eighth of the East Antarctic Ice Sheet and contains a volume equivalent to nearly 7 meters of potential sea level rise, greater than the entire West Antarctic Ice Sheet. This nearly completely unexplored region is the single largest and least understood marine glacial system that is potentially unstable. Despite intense scrutiny of marine based systems in the West Antarctic Ice Sheet, little is known about the Totten Glacier system. This study will add substantially to the meager oceanographic and marine geology and geophysics data available in this region, and will significantly advance understanding of this poorly understood glacial system and its potentially sensitive response to environmental change.

Independent, space-based platforms indicate accelerating mass loss of the Totten system. Recent aerogeophysical surveys of the Aurora Subglacial Basin, which contains the deepest ice in Antarctica and drains into the Totten system, have provided the subglacial context for measured surface changes and show that the Totten Glacier has been the most significant drainage pathway for at least two previous ice flow regimes. However, the offshore context is far less understood. Limited physical oceanographic data from the nearby shelf/slope break indicate the presence of Modified Circumpolar Deep Water within a thick bottom layer at the mouth of a trough with apparent access to Totten Glacier, suggesting the possibility of sub-glacial bottom inflow of relatively warm water, a process considered to be responsible for West Antarctic Ice Sheet grounding line retreat. This project will conduct a ship-based marine geologic and geophysical survey of the region, combined with a physical oceanographic study, in order to evaluate both the recent and longer-term behavior of the glacial system and its relationship to the adjacent oceanographic system. This endeavor will complement studies of other Antarctic ice shelves, oceanographic studies near the Antarctic Peninsula, and ongoing development of ice sheet and other ocean models.

Person	Role
Orsi, Alejandro	Investigator
Huber, Bruce	Investigator
Leventer, Amy	Investigator
Domack, Eugene Walter	Investigator

Antarctic Integrated System Science	Award # 1430550
Antarctic Integrated System Science	Award # 1143836
Antarctic Integrated System Science	Award # 1143834
Antarctic Integrated System Science	Award # 1143833

USAP-1143834
USAP-1430550
USAP-1143836
USAP-1143833_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	NBP14-02 JPC-55 foraminifer assemblage data	None	exist
USAP-DC	NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data	None	exist
USAP-DC	NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data	None	exist
USAP-DC	NBP1402 diatom data	None	deprecated
USAP-DC	NBP1402 Final CTD data	None	exist
USAP-DC	NBP1402 Lowered ADCP data	None	exist
USAP-DC	Sabrina Coast mooring data - sediment trap mooring 2014	None	exist
USAP-DC	NBP1402 Final UCTD data	None	exist
USAP-DC	AU1402 Final UCTD data	None	exist
USAP-DC	AU1402 mooring data	None	exist
USAP-DC	NBP1402 diatom data	None	exists
USAP-DC	Bottom photos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402	None	exists
USAP-DC	Near-bottom Videos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402	None	exists
USAP-DC	NBP1402 JPC43 Diatom Data	None	exists

1. Smith, C., Warny, S., Shevenell, A.E., Gulick, S.P. and Leventer, A., 2018. New species from the Sabrina Flora: an early Paleogene pollen and spore assemblage from the Sabrina Coast, East Antarctica. Palynology, pp.1-10. (doi:10.1080/01916122.2018.1471422)
2. Fernandez, R., Gulick, S., Domack, E., Montelli, A., Leventer, A., Shevenell, A., & Frederick, B. (2018). Past ice stream and ice sheet changes on the continental shelf off the Sabrina Coast, East Antarctica. Geomorphology, 317, 10–22. (doi:10.1016/j.geomorph.2018.05.020)
3. Armbrecht, L. H., Eriksen, R., Leventer, A., & Armand, L. K. (2017). First observations of living sea-ice diatom agglomeration to tintinnid loricae in East Antarctica. Journal of Plankton Research, 39(5), 795–802. (doi:10.1093/plankt/fbx036)
4. Beszteri, B., Allen, C., Almandoz, G. O., Armand, L., Barcena, M. Á., Cantzler, H., … Rigual Hernández, A. S. (2018). Quantitative comparison of taxa and taxon concepts in the diatom genusFragilariopsis: a case study on using slide scanning, multiexpert image annotation, and image analysis in taxonomy1. Journal of Phycology, 54(5), 703–719. (doi:10.1111/jpy.12767)
5. Smik, L., Belt, S. T., Lieser, J. L., Armand, L. K., & Leventer, A. (2016). Distributions of highly branched isoprenoid alkenes and other algal lipids in surface waters from East Antarctica: Further insights for biomarker-based paleo sea-ice reconstruction. Organic Geochemistry, 95, 71–80. (doi:10.1016/j.orggeochem.2016.02.011)
6. Frederick, B. C., Young, D. A., Blankenship, D. D., Richter, T. G., Kempf, S. D., Ferraccioli, F., & Siegert, M. J. (2016). Distribution of subglacial sediments across the Wilkes Subglacial Basin, East Antarctica. Journal of Geophysical Research: Earth Surface, 121(4), 790–813. (doi:10.1002/2015jf003760)
7. Mawbey, E. M., Hendry, K. R., Greaves, M. J., Hillenbrand, C.-D., Kuhn, G., Spencer-Jones, C. L., … Smith, J. A. (2020). Mg/Ca-Temperature Calibration of Polar Benthic foraminifera species for reconstruction of bottom water temperatures on the Antarctic shelf. Geochimica et Cosmochimica Acta, 283, 54–66. (doi:10.1016/j.gca.2020.05.027)
8. Rontani, J.-F., Smik, L., Belt, S. T., Vaultier, F., Armbrecht, L., Leventer, A., & Armand, L. K. (2019). Abiotic degradation of highly branched isoprenoid alkenes and other lipids in the water column off East Antarctica. Marine Chemistry, 210, 34–47. (doi:10.1016/j.marchem.2019.02.004)
9. Lawler, K.-A., Cortese, G., Civel-Mazens, M., Bostock, H., Crosta, X., Leventer, A., … Armand, L. K. (2021). The Southern Ocean Radiolarian (SO-RAD) dataset: a new compilation of modern radiolarian census data. Earth System Science Data, 13(11), 5441–5453. (doi:10.5194/essd-13-5441-2021)
10. Lawler, K.-A., Cortese, G., Civel-Mazens, M., Bostock, H., Crosta, X., Leventer, A., … Armand, L. K. (2021). The Southern Ocean RADiolarian (SO-RAD) dataset: a new compilation of modern radiolarian census data. (doi:10.5194/essd-2021-148)
11. Orsi, A. H., & Webb, C. J. (2022). Impact of Sea Ice Production off Sabrina Coast, East Antarctica. Geophysical Research Letters, 49(5). Portico. (doi:10.1029/2021gl095613)