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POLENET The Polar Earth Observatory Network, or POLENET, is a recently proposed GPS/Seismic network, aimed at observing the Antarctic glaciologic and geologic system using a multidisciplinary and internationally-coordinated approach. An observatory-style backbone network of 18 co-located, continuously-recording GPS and broadband seismic sites across West Antarctica, as well as a 2-3 year GPS and seismic “IPY-only” deployment has been proposed (figure 1). The co-location of GPS and seismic sensors provides important science synergies and significant logistical advantages. Cooperation of the GPS and seismic PIs, UNAVCO, and IRIS will allow development and deployment of the next-generation power and communication systems optimized for remote deployments in extreme environments. In
order to refine estimates of recent ice mass change of the West Antarctic
Ice Sheet, we will measure isostatic rebound with GPS, constrain mantle
rheology through seismic studies, and dramatically improve continental-scale
rebound model predictions used to correct ice mass trends derived from
satellite altimetry and time-varying gravity. Both the viscoelastic and
elastic response from mass change can be modeled from continuous GPS measurements,
allowing for better estimates of Antarctica’s contribution to global
sea level change. Seismological investigations, integrated with results
from the geodetic studies, will provide first-order constraints on geological/tectonic
parameters important for understanding ice sheet dynamics in West Antarctica.
New seismic data will be used to develop high-resolution seismic tomographic
images, seismic receiver functions will be used to map the sediment thickness
distribution beneath the ice sheet, and recordings of glacial earthquakes
will help to constrain short-term slip events that are important for understanding
ice sheet dynamics.
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