TY  - STD
AU  - Durand G, Gagliardini O.
PY  - 2011//
TI  - Impact of bedrock description on modeling ice sheet dynamics
BT  - Geophys. Res. Lett.
SP  - L20501-
VL  - 38
IS  - 20
PB  - AGU
KW  - DEM
KW  - bedrock
KW  - ice sheet
KW  - 0726 Cryosphere: Ice sheets
KW  - 0774 Cryosphere: Dynamics
KW  - 0798 Cryosphere: Modeling (1952
KW  - 4316)
KW  -
N2  - Recent glaciological surveys have revealed a significant increase of ice discharge from polar ice caps into the ocean. In parallel, ice flow models have been greatly improved to better reproduce current changes and forecast the future behavior of ice sheets. For these models, surface topography and bedrock elevation are crucial input parameters that largely control the dynamics and the ensuing overall mass balance of the ice sheet. For obvious reasons of inaccessibility, only sparse and uneven bedrock elevation data is available. This raw data is processed to produce Digital Elevation Models (DEMs) on a regular 5 km grid. These DEMs are used to constrain the basal boundary conditions of all ice sheet models. Here, by using a full-Stokes finite element code, we examine the sensitivity of an ice flow model to the accuracy of the bedrock description. In the context of short-term ice sheet forecast, we show that in coastal regions, the bedrock elevation should be known at a resolution of the order of one kilometer. Conversely, a crude description of the bedrock in the interior of the continent does not affect modeling of the ice outflow into the ocean. These findings clearly indicate that coastal regions should be prioritized during future geophysical surveys. They also indicate that a paradigm shift is required to change the current design of DEMs describing the bedrock below the ice sheets: they must give users the opportunity to incorporate high-resolution bedrock elevation data in regions of interest.
SN  - 0094-8276
L1  - https://sciences.ipev.fr/proposals/uploads/files/1053/2012/BedRock.pdf
UR  - http://dx.doi.org/10.1029/2011GL048892
N1  - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=3452), last updated on Tue, 30 Nov 1999 00:00:00 +0100
ID  - DurandG2011
ER  -