Ocean access beneath the southwest tributary of Pine Island Glacier, West Antarctica

• Published in: Annals of Glaciology
• Main Authors: Dustin M. Schroeder, Andrew M. Hilger, John D. Paden, Duncan A. Young, Hugh F. J. Corr
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2018
• Subjects: glaciological instruments and methods; ground-penetrating radar; ice/ocean interactions; radio-echo sounding; remote sensing; Meteorology. Climatology; QC851-999; Antarctic; West Antarctica; Amundsen Sea; West Antarctic Ice Sheet; Pine Island Glacier; Thwaites Glacier; Annals of Glaciology; Antarc*; Antarctica; Ice Sheet; Ice Shelf; Pine Island
• Online Access: https://doi.org/10.1017/aog.2017.45; https://doaj.org/article/7f50ce51262d47e89164a4b8944ccb95

The catchments of Pine Island Glacier and Thwaites Glacier in the Amundsen Sea Embayment are two of the largest, most rapidly changing, and potentially unstable sectors of the West Antarctic Ice Sheet. They are also neighboring outlets, separated by the topographically unconfined eastern shear margin of Thwaites Glacier and the southwest tributary of Pine Island Glacier. This tributary begins just downstream of the eastern shear margin and flows into the Pine Island ice shelf. As a result, it is a potential locus of interaction between the two glaciers and could result in cross-catchment feedback during the retreat of either. Here, we analyze relative basal reflectivity profiles from three radar sounding survey lines collected using the UTIG HiCARS radar system in 2004 and CReSIS MCoRDS radar system in 2012 and 2014 to investigate the extent and character of ocean access beneath the southwest tributary. These profiles provide evidence of ocean access ~12 km inland of the 1992–2011 InSAR-derived grounding line by 2014, suggesting either retreat since 2011 or the intrusion of ocean water kilometers inland of the grounding line.