Bathymetry of the Amundsen Sea Embayment sector of West Antarctica from Operation IceBridge gravity and other data

• Published in: Geophysical Research Letters
• Main Authors: Millan, Romain, Rignot, Eric, Bernier, Vincent, Morlighem, Mathieu, Dutrieux, Pierre
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: eScholarship, University of California 2017
• Subjects: Climate Action; Meteorology & Atmospheric Sciences; Amundsen Sea; Antarc*; Antarctica; Ice Shelf; Ice Shelves; Pine Island; West Antarctica
• Online Access: https://escholarship.org/uc/item/9jq0j78c; https://escholarship.org/content/qt9jq0j78c/qt9jq0j78c.pdf; https://doi.org/10.1002/2016gl072071

We employ airborne gravity data from NASA's Operation IceBridge collected in 2009–2014 to infer the bathymetry of sub–ice shelf cavities in front of Pine Island, Thwaites, Smith, and Kohler glaciers, West Antarctica. We use a three-dimensional inversion constrained by multibeam echo sounding data offshore and bed topography from a mass conservation reconstruction on land. The seamless bed elevation data refine details of the Pine Island sub–ice shelf cavity, a slightly thinner cavity beneath Thwaites, and previously unknown deep (>1200m) channels beneath the Crosson and Dotson ice shelves that shallow (500m and 750m, respectively) near the ice shelf fronts. These sub–ice shelf channels define the natural pathways for warm, circumpolar deep water to reach the glacier grounding lines, melt the ice shelves from below, and constrain the pattern of past and future glacial retreat.