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Monitoring Antarctic ice loss
from space
Fernando S. Paolo* Helen A. Fricker Laurie Padman
Scripps Student Symposium 2014 | NASA | *[email protected]
In the news:
.com
● How all works (the science)
● The floating ice-shelves (the why)
● The challenge in observing (the how)
● Ok, show me some results!
In this talk
Geometry of the bed constrains stability!
Ice sheet configuration
Floating
ice shelf
>80% of all
ice on Earth
Rivers of ice!
The marine-ice-sheet instability(or What’s going on in West Antarctica)
Flow ∝ Thickness n>3
Retrograde slope=
Unstable
gain
loss
Once retreat starts is self-sustained
The missing piece:
The role of the ice shelves
Ice-shelf buttressing → the key to stability
How do we observe changes in ice
shelves at a continental scale?
Observation principle
Δh/Δt = func(tides, penet., backscat., pressure, SLR, MDT,..., thickness)
Millions
of data
points!
What do these observations tell us?
(18 years of change)
Regionalthickness change1994-2012
-0.7 m/year
-1.5 m/year
First time with this coverage, resolution and time span!
● West Antarctica is already losing ice at an accelerated
rate.
● Collapse of the entire WAIS is not guaranteed, but quite
plausible.
● There is a direct link between ocean warming and ice-
loss acceleration.
● The ice-sheet behaviour is the largest uncertainty in
predicting sea-level rise.
What do we know after all?
Ice-shelf vertical motion
Δh/Δt = func(tides, penetration, backscatter, pressure, sea-level, thickness,...)
Ice-sheet contribution
to sea-level rise
10%
30%
60%
>80%
3 mm/year
