1. OBSERVING EVOLVING ANTARCTIC ICE SHELVES
CONDITION USING MULTI-TEMPORAL RADAR SOUNDING
Winnie Chu (wchu38@gatech.edu)
School of Earth & Atmospheric Sciences,
Georgia Institute of Technology
MOTIVATION & GOALS
• Ice shelves are
constantly
changing and
yet it is difficult
to observe
changes
beneath the ice
Goal:
Surface fractures &
rifts from satellite
images
Use radar sounding to characterize ice shelf basal
condition (e.g., channels evolution, melt rates)
RADAR METHODOLOGY
By using radar
sounding, we can direct
observe changes in ice
shelf basal features,
such as basal channels
1. Surface echo power
1
2
3
Constrain shelf surface
roughness, rifts, crevasses
2. Englacial attenuation loss
Related to conductivity
contrast due to temperature
and impurities
3. Basal echo power
Use specular vs. diffuse power,
reflectivity etc. to infer meltwater
layers, freeze-on, basal roughness
EX. 1: BASAL MELT RATES EX. 2: HISTORICAL CHANGES
By relating radar englacial
attenuation to ice column
temperature
Na
∂2
T
∂z2
+
w
κ
∂T
∂z
= 0
Relate basal melt rate to ice
temperature by using 1-D heat
advection and diffusion model
·
m
Increasing
melting
Attenuation varies with temperature;
thus we can relate and basal melt
Na
Estimated ocean-driven basal
melt rates for Ross Ice Shelf,
East Antarctica
Transfer modern analysis to
archival airborne data
collected in the 70s
Ross Ice shelf thickness in
1974 prior to warming
GT Glacier Geophysics Lab
website
More historical radar data can be found:
This work is supported by NASA’s Earth Science Technology Office NNH21ZDA001N, 80NSSC
22K0661 and National Science Foundation Office of Polar Programs OPP 2049332
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