MS Thesis: Investigating the Timing of Deglaciation and the Efficiency of Subglacial Erosion in Central-Western Greenland

OVERVIEW

The Greenland Ice Sheet has been far from stable over time; in fact, its size seems to have varied substantially with periods of warm and cool climate. Understanding this dynamic system is especially important today, as the Greenland Ice Sheet will likely have a significant melting response due to anthropogenic climate change. By determining how the ice sheet has reacted to past climate changes during the Quaternary, we will be better able to anticipate how it will react climate changes in the present and in the future. This project uses various forms of cosmogenic nuclide dating to determine how ice sheet extent has varied over time. My portion of the project focused on quantifying subglacial erosion efficiency and ice retreat rates at the end of the last ice age about 11,000 years ago.

The field team at the ice margin near Kangerlussuaq (July 2008).

The world's windiest campsite at the ice margin near Kangerlussuaq (July 2008).

View of the Upernavik landscape: table-top highlands separated by deep fjords (July 2008).

Sampling a low-elevation boulder near Upernavik (July 2008).

Sampling a high-elevation bedrock surface in windy conditions near Upernavik (July 2008).

Fast and furious heli-supported sampling near Ilulissat (July 2008).

Upernavik, Greenland, on the cover of GSA Bulletin (Corbett et al., 2013)

PUBLICATIONS

Corbett, L.B., Bierman, P.R., Graly, J.A., Neumann, T.A., and Rood, D.H. 2013. Constraining landscape history and glacial erosivity using paired cosmogenic nuclides in Upernavik, Northwest Greenland. Geological Society of America Bulletin 125: 1539-1553. (On the cover of the September 2013 GSA Bulletin, above; also featured on NBC, LiveScience, and History Channel in August 2013).

Young, N.E., Briner, J.P., Rood, D.H., Finkel, R.C., Corbett, L.B., and Bierman, P.R. 2013. Age of the Fjord Stade moraines in the Disko Bugt region, western Greenland, and the 9.3 and 8.2 ka cooling events. Quaternary Science Reviews 60: 76-90.

Corbett, L.B., Young, N.E., Bierman, P.R., Briner, J.P., Graly, J.A., Neumann, T.A, and Rood, D.H. 2011. Paired bedrock and boulder 10Be concentrations resulting from early Holocene ice retreat near Jakobshavn Isfjord, western Greenland. Quaternary Science Reviews 30: 1739-1749.

CONFERENCE ABSTRACTS

Corbett, L.B., Bierman, P.R., Graly, J.A., Neumann, T.A., and Rood, D.H. 2013. Using cosmogenic nuclides to study subglacial erosion efficiency and landscape history in western Greenland. Northeastern Geological Society of America Meeting, Bretton Woods NH. Geological Society of America Abstracts with Programs 45(1): 85.

Bierman, P.R., Rood, D.H., and Corbett, L.B. 2012. High-precision, high-resolution, post-glacial emergence curves for southern Greenland generated with in situ cosmogenic 10-Be (invited). American Geophysical Union Fall Meeting, San Francisco, CA. Abstract ID C53E-06.

Corbett, L.B., Bierman, P.R., Graly, J.A., Neumann, T.A., Rood, D.H., and Finkel, R.C. 2010. Glacial erosion efficiency, early Holocene ice retreat rates, and interglacial exposure: new cosmogenic 10Be data from three sites in western Greenland. American Geophysical Union Fall Meeting, San Francisco, CA. Eos Transactions AGU 91(52): C23B-0612.

Corbett, L.B., Young, N.A., Briner, J.P., Bierman, P.R., Graly, J.A., Neumann, T.A., and Rood, D.H. 2010. Using in situ cosmogenic 10Be to understand deglaciation timing and glacial erosion efficiency near Jakobshavn Icefjord, Western Greenland. Geological Society of America National Meeting, Denver, CO. Geological Society of America Abstracts with Programs 42(5): 244.

Bierman, P.R., Corbett, L.B., Reusser, L.J., Graly, J.A., Finkel, R.C., Rood, D.H., and Neumann, T.A. 2010. River response to Greenland deglaciation monitored with cosmogenic 10Be: A new way of detecting and quantifying post-glacial emergence. International Polar Year Oslo Science Conference, Oslo, Norway.

Corbett, L.B., Bierman, P.R., Graly, J.A., Neumann, T.A., Rood, D.H., and Finkel, R.C. 2010. When did the ice leave Upernavik and how much rock was eroded: first in situ cosmogenic 10Be measurements from Northwestern Greenland. International Polar Year Oslo Science Conference, Oslo, Norway.

Bierman, P.R., Corbett, L.B., Reusser, L.J., Graly, J.A., Finkel, R.C., Rood, D.H., and Neumann, T.A. 2010. Quantifying post-glacial emergence at Kangerlussuaq, Greenland, using 10Be dating of bedrock forms exposed by river incision. International Arctic Workshop, Winter Park, CO. International Arctic Workshop Program and Abstracts: 36-38.

Corbett, L.B., Bierman, P.R., Graly, J.A., Neumann, T.A., Rood, D.H., and Finkel, R.C. 2010. In situ cosmogenic 10Be estimates of deglaciation timing and glacial erosion efficiency, Upernavik, Western Greenland. International Arctic Workshop, Winter Park, CO. International Arctic Workshop Program and Abstracts: 57-58.

Corbett, L.B., Bierman, P.R., Graly, J.A., Neumann, T.A., Rood, D.H., and Finkel, R.C. 2009. In situ 10Be estimates of deglaciation timing and glacial erosion efficiency, Western Greenland. Geological Society of America National Meeting, Portland, OR. Geological Society of America Abstracts with Programs 41(7): 620.