Subglacial roughness of the West Antarctic Ice Sheet

• Main Authors: D. A. Young, D. D. Blankenship, J. W. Holt
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Siple; Siple Coast; Thwaites Glacier; West Antarctic Ice Sheet; Antarc*; Ice Sheet
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.539.257; http://pubs.usgs.gov/of/2007/1047/ea/of2007-1047ea056.pdf

Summary We use basal roughness, a property accessible to airborne ice penetrating radar, to examine the dynamics of the West Antarctic Ice Sheet. We examine roughness through analysis of the along track variability of basal elevation profiles collected over the Siple Coast and the Thwaites Glacier catchment, at length scales between 400 meters and 4 kilometers. There are significant differences in the patterns of roughness between catchments. A one-to-one correlation between roughness and proposed sedimentary basins identified in potential fields data in the Siple Coast is not apparent. However, roughness does systematically decrease downstream, likely reflecting the effect of mobile tills. Under Thwaites Glacier, smooth areas are more localized, and restricted to the interior. In addition, we find that in the Siple Coast region, the plateaus underlying the major interstream ice ridges are remarkably smooth at all length scales, while flat bedrock platforms do not exist near Thwaites Glacier.