Grounding‐Zone Flow Variability of Priestley Glacier, Antarctica, in a Diurnal Tidal Regime
نویسندگان
چکیده
Tidal modulation of ice streams and their adjacent shelves is a real-world experiment to understand ice-dynamic processes. We observe the dynamics Priestley Glacier, Antarctica, using Terrestrial Radar Interferometry (TRI) GNSS. Ocean tides are predominantly diurnal but horizontal GNSS displacements also oscillate semi-diurnally. The oscillations strongest in shelf tidal signatures decay near-linearly TRI data over 10 km upstream grounding line. flexing observed 6 line including cm-scale uplift. migration small 40% thickness. frequency doubling relative ocean consistent with variable ice-shelf buttressing demonstrated visco-elastic Maxwell model. Taken together, this supports previously hypothesized flexural softening grounding-zone through offers new observational constraints for role rheology buttressing.
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ژورنال
عنوان ژورنال: Geophysical Research Letters
سال: 2021
ISSN: ['1944-8007', '0094-8276']
DOI: https://doi.org/10.1029/2021gl093853