Tidal Motion of west ice shelf
Here's a quick animation of an exaggerated (100x) tidal motion of
West Ice Shelf, Antarctica. Here Bedmap2 data are forced with
Laurie Padman's CATS2008b tide prediction model. You'll notice
that the ice shelf does not rise and fall as a solid unit; instead, at
times parts are rising while other sections are falling. A major
simplification here is that the ice shelf hinges upon a clearly-defined
grounding line, and any given parcel of ice exhibits either 100% of
tidal flexure, or none at all. In reality, the grounding line is
more of a broad grounding zone,
where the ice may move only a small fraction of the full tidal
displacement, or vertical motion may even be opposite in sign of the
nearby tidal forcing.
Cross-Track Radar Uncertainty Over Thwaites Glacier
Top Figure: Cross-track glacial bed topography along a 98 km flight
line over a synthetic bed modeled after highland Thwaites Glacier.
Black lines indicate extents of area illuminated by radar.
Bottom Figure: Along-track bed topography. "Phantom bedrock" is seen by the radar when the nearest reflector is off-nadir in the cross-track direction. For example, at an along-track distance of 90 km (0:38 in this video), a feature ~1 km to the left of the aircraft is seen as the closest reflector. Red star indicates aircraft position.
Synthetic topography generated by John Goff at the University of Texas Institute for Geophysics.