Unsteady flow inferred for Thwaites Glacier, and comparison with Pine Island Glacier, West Antarctica

• Published in: Journal of Glaciology
• Main Authors: Bamber, Jonathan, Rignot, Eric
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: eScholarship, University of California 2002
• Subjects: Physical Geography and Environmental Geoscience; Meteorology & Atmospheric Sciences; Antarc*; Antarctica; Journal of Glaciology; Pine Island; Pine Island Glacier; Thwaites Glacier; West Antarctica
• Online Access: https://escholarship.org/uc/item/1p17h4rz; https://escholarship.org/content/qt1p17h4rz/qt1p17h4rz.pdf; https://doi.org/10.3189/172756502781831395

We present a comparison of surface velocities in 1996, derived from interferometric synthetic aperture radar, with an estimate of the long-term, depth-averaged velocity based on the assumption of steady-state flow for both Pine Island Glacier and its neighbour, Thwaites Glacier, West Antarctica. The results show that the former was close to balance conditions in 1996 (within 9%). The ice flux and velocity of the latter is significantly different in magnitude and distribution from that required to maintain the basin in a state of mass balance over the long term. The balance flux was found to be 32 ± 19% less than the measured outgoing flux. We conclude that the mass imbalance and dramatic difference in the pattern of flow is most likely due to a substantial change in the flow regime of Thwaites Glacier in the recent past.