The ECSU Summer
2006 Undergraduate Research Experience (URE) Holistic Ice Sheet
Modeling Team studied a first-order analytic model of a continental
ice sheet, based on balancing gravitational pressure forces against
internal compressive and tensile stresses and externally applied
basal and side shearing stresses, to derive structural characteristics
of a continental ice sheet. A simplified first-order model for
ice thickness, based only on geometric force balance considerations
were compared to ice thickness data obtained by an aerial ice
penetrating RADAR survey of the Antarctic's Byrd Ice Stream The
first-order model results were compared to those of a higher order
analytic approximation used to interpret the data.
The simple first-order
model may be expanded to include mass balance considerations and
a parameterized description of coupling between the ice basal
surface and bed texture roughness and topography. The expanded
first-order model would yield insight into the dynamic variations
in ice sheet and ice stream behavior resulting from changes in
ice accumulation and ablation rates that may be possible consequences
of Global Climate Warming. The full, first-order model yields
insight into ice sheet evolution from its genesis as a grounded
continental sheet frozen to its bed, to a partially grounded ice
stream flowing to its terminus: a calving ice shelf.