USAP-DC

The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.

Subglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.

Person	Role
Rosenheim, Brad	Investigator
Fricker, Helen	Investigator
Priscu, John	Investigator and contact
Leventer, Amy	Investigator
Dore, John	Co-Investigator
Lyons, W. Berry	Investigator
Christner, Brent	Investigator
Gardner, Christopher B.	Researcher

Antarctic Glaciology	Award # 1543537
Antarctic Integrated System Science	Award # 1543537
Antarctic Glaciology	Award # 1543453
Antarctic Integrated System Science	Award # 1543453
Antarctic Instrumentation and Support	Award # 1543441
Antarctic Integrated System Science	Award # 1543441
Antarctic Glaciology	Award # 1543405
Antarctic Integrated System Science	Award # 1543405
Antarctic Glaciology	Award # 1543396
Antarctic Integrated System Science	Award # 1543396
Antarctic Glaciology	Award # 1543347
Antarctic Integrated System Science	Award # 1543347

USAP-1543537_1

Deployment	Type
SALSA	field camp

None in the Database

Repository	Title (link)	Format(s)	Status
UNAVCO	Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset	Excel; Binary	exist
UNAVCO	Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset	Excel; Binary	exist
UNAVCO	Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset	Excel; Binary	exist
UNAVCO	Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset	Excel; Binary	exist
UNAVCO	Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset	Excel; Binary	exist
UNAVCO	Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset	Excel; Binary	exist
OSU-MGR	Salsa sediment cores	Excel; Binary	exists
NCBI GenBank	Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995)	Excel; Binary	exists
GenBank	Mercer Subglacial Lake water column viral metagenomic sequencing	Binary	exist
USAP-DC	Isotopic data from Whillans Ice Stream grounding zone, West Antarctica	Excel; Binary	exists
USAP-DC	Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland	Excel; Binary	exists
USAP-DC	Mercer Subglacial Lake (SLM) noble gas and isotopic data	Excel; Binary	exists
USAP-DC	CTD data from Mercer Subglacial Lake and access borehole	Excel	exists
USAP-DC	Discrete bulk sediment properties data from Mercer Subglacial Lake	Excel	exists
USAP-DC	Water column biogeochemical data from Mercer Subglacial Lake	Excel	exists
USAP-DC	Sediment porewater properties data from Mercer Subglacial Lake	Excel	exists
USAP-DC	Mercer Subglacial Lake radiocarbon and stable isotope data	Excel	exists

1. Rutishauser, A., Blankenship, D. D., Sharp, M., Skidmore, M. L., Greenbaum, J. S., Grima, C., … Young, D. A. (2018). Discovery of a hypersaline subglacial lake complex beneath Devon Ice Cap, Canadian Arctic. Science Advances, 4(4), eaar4353. (doi:10.1126/sciadv.aar4353)
2. Hawkings, J. R., Skidmore, M. L., Wadham, J. L., Priscu, J. C., Morton, P. L., … Hatton, J. E. (2020). Enhanced trace element mobilization by Earth’s ice sheets. Proceedings of the National Academy of Sciences, 117(50), 31648–31659. (doi:10.1073/pnas.2014378117)
3. Santibáñez, P. A., Michaud, A. B., Vick‐Majors, T. J., D’Andrilli, J., Chiuchiolo, A., Hand, K. P., & Priscu, J. C. (2019). Differential Incorporation of Bacteria, Organic Matter, and Inorganic Ions Into Lake Ice During Ice Formation. Journal of Geophysical Research: Biogeosciences, 124(3), 585–600. (doi:10.1029/2018jg004825)
4. Venturelli, R. A., Siegfried, M. R., Roush, K. A., Li, W., Burnett, J., Zook, R., … Rosenheim, B. E. (2020). Mid‐Holocene Grounding Line Retreat and Readvance at Whillans Ice Stream, West Antarctica. Geophysical Research Letters, 47(15). (doi:10.1029/2020gl088476)
5. Li, W., Dore, J. E., Steigmeyer, A. J., Cho, Y., Kim, O., Liu, Y., … Priscu, J. C. (2019). Methane production in the oxygenated water column of a perennially ice‐covered Antarctic lake. Limnology and Oceanography, 65(1), 143–156. (doi:10.1002/lno.11257)
6. Siegfried, M. R., Medley, B., Larson, K. M., Fricker, H. A., & Tulaczyk, S. (2017). Snow accumulation variability on a West Antarctic ice stream observed with GPS reflectometry, 2007–2017. Geophysical Research Letters, 44(15), 7808–7816. (doi:10.1002/2017gl074039)
7. Bienert, N. L., Schroeder, D. M., Peters, S. T., & Siegfried, M. R. (2020). Processing-Based Synchronization Approach for Bistatic Radar Glacial Tomography. IGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium. (doi:10.1109/igarss39084.2020.9323969)
8. Bienert, N. L., Schroeder, D. M., Peters, S. T., MacKie, E. J., Dawson, E. J., Siegfried, M., … Christoffersen, P. (2022). Post-Processing Synchronized Bistatic Radar for Long Offset Glacier Sounding. IEEE Transactions on Geoscience and Remote Sensing, 1–1. (doi:10.1109/tgrs.2022.3147172)
9. Davis, C.L., Venturelli, R.A., Michaud, A.B. et al. Biogeochemical and historical drivers of microbial community composition and structure in sediments from Mercer Subglacial Lake, West Antarctica. ISME COMMUN. 3, 8 (2023). https://doi.org/10.1038/s43705-023-00216-w (doi:10.1038/s43705-023-00216-w)
10. Rosenheim, B. E., Michaud, A. B., Broda, J., Gagnon, A., Venturelli, R. A., Campbell, T. D., Leventer, A., Patterson, M., Siegfried, M. R., Christner, B. C., Duling, D., Harwood, D., Dore, J. E., Tranter, M., Skidmore, M. L., & Priscu, J. C. (2023). A method for successful collection of multicores and gravity cores from Antarctic subglacial lakes. Limnology and Oceanography: Methods. Portico. (doi:10.1002/lom3.10545)
11. Michaud, A. B., & Priscu, J. C. (2023). Sediment oxygen consumption in Antarctic subglacial environments. Limnology and Oceanography. Portico. (doi:10.1002/lno.12366)