  Across the ANET GNSS network, decadal mass loss of the Antarctic ice sheet
drives elastic uplift rates of up to 20 mm/yr. We explore, for the first time,
the viability of using elastic deformation observed in the ANET GNSS network to
constrain ice mass changes in Antarctica. We begin by estimating which regions
of ice mass loss contribute to the elastic deformation observed at each ANET
GNSS site. This is done using an observer-centric model of elastic deformation,
which we call a Load Sensitivity Kernel (LSK). Using this approach, we find
that the elastic deformation at the majority of ANET sites is dominated by
far-field mass change. Over 70% of ANET sites require ice mass change within a
radius of 200km or greater to be included before 90% of the site's elastic
deformation is recovered. We show that the difference between LSKs of a pair of
neighboring GNSS receivers can be used to localize the near-field mass change
responsible for the differential displacement. Finally, we generalize this in a
novel approach that uses an arbitrary number of GNSS sites. In this approach,
LSKs of each site are weighted and added in a linear series. These weights are
optimized such that the elastic deformation from mass change outside a Region
of Interest is minimized. We demonstrate that 7 ANET GNSS sites in the Amundsen
Sea region can isolate the elastic deformation, in both the vertical and
horizontal components, that results exclusively from PIG's mass loss and/or the
losses of the PSK glaciers. With the current GNSS receiver distribution, the
east component of elastic deformation due to mass change at Thwaites can be
expressed relative to mass changes at PSK. Our results demonstrate that the
current ANET configuration can use elastic deformation to constrain ice mass
changes in Antarctica, especially in regions with relatively dense clusters of
GNSS.
