Dynamics and mass balance of Taylor Glacier, Antarctica: 1. Geometry and surface velocities

• Published in: Journal of Geophysical Research. B. Solid Earth Vol. 114; no. F4
• Main Authors: Kavanaugh, J. L., Cuffey, K. M., Morse, D. L., Conway, H., Rignot, E.
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01-12-2009; American Geophysical Union
• Subjects: Antarctica; Bedrock; Cryosphere; Earth sciences; Earth, ocean, space; Elevation; Exact sciences and technology; Geomorphology; glacier dynamics; glacier erosion; Glaciers; Global Positioning System; Outlets; Paleoclimate; Satellite navigation systems; Surface velocity; Valleys; Narrows; New York; Taylor Glacier; United States; polar regions; Antarctica; Victoria Land; Antarctic ice sheet; Antarctica, Victoria Land, McMurdo Dry Valley; geomorphology; mass balance; thickness; Spot; ice; undulation; North America; paleoclimate; cascades; dynamics; ecology; bedrock; Outlet glacier; flow; Synthetic aperture radar; troughs; models; interferometry; topography; climate; velocity; dry valleys; ground-penetrating radar; Global Positioning System; Interannual variation; geometry
• DOI: 10.1029/2009JF001309
• EISSN: 2156-2202; 2169-9011
• ISSN: 0148-0227; 2169-9003

Taylor Glacier, Antarctica, exemplifies a little‐studied type of outlet glacier, one that flows slowly through a region of rugged topography and dry climate. This glacier, in addition, connects the East Antarctic Ice Sheet with the McMurdo Dry Valleys, a region much studied for geomorphology, paleoclimate, and ecology. Here we report extensive new measurements of surface velocities, ice thicknesses, and surface elevations, acquired with InSAR, GPS, and GPR. The latter two were used to construct elevation models of the glacier's surface and bed. Ice velocities in 2002–2004 closely matched those in 2000 and the mid‐1970s, indicating negligible interannual variations of flow. Comparing velocities with bed elevations shows that, along much of the glacier, flow concentrates in a narrow axis of relatively fast flowing ice that overlies a bedrock trough. The flow of the glacier over major undulations in its bed can be regarded as a “cascade”; it speeds up over bedrock highs and through valley narrows and slows down over deep basins and in wide spots. This pattern is an expected consequence of mass conservation for a glacier near steady state. Neither theory nor data from this Taylor Glacier study support the alternative view, recently proposed, that an outlet glacier of this type trickles slowly over bedrock highs and flows fastest over deep basins.