 |
| Titel |
Diagnostic and prognostic simulations with a full Stokes model accounting for superimposed ice of Midtre Lovénbreen, Svalbard |
| VerfasserIn |
T. Zwinger, J. C. Moore |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1994-0416
|
| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 3, no. 2 ; Nr. 3, no. 2 (2009-11-19), S.217-229 |
| Datensatznummer |
250000939
|
| Publikation (Nr.) |
 copernicus.org/tc-3-217-2009.pdf |
|
|
|
|
|
| Zusammenfassung |
We present steady state (diagnostic) and transient (prognostic)
simulations of Midtre Lovénbreen, Svalbard performed with the
thermo-mechanically coupled full-Stokes code Elmer. This glacier has
an extensive data set of geophysical measurements available spanning
several decades, that allow for constraints on model
descriptions. Consistent with this data set, we included a simple
model accounting for the formation of superimposed ice. Diagnostic
results indicated that a dynamic adaptation of the free surface is
necessary, to prevent non-physically high velocities in a region of
under determined bedrock depths.
Observations from ground penetrating radar of the basal thermal state agree
very well with model predictions, while the dip angles of isochrones in radar
data also match reasonably well with modelled isochrones, despite the numerical
deficiencies of estimating ages with a steady state model.
Prognostic runs for 53 years,
using a constant accumulation/ablation pattern starting from the
steady state solution obtained from the configuration of the 1977 DEM
show that: 1 the unrealistic velocities in the under determined parts
of the DEM quickly damp out; 2 the free surface evolution matches well
measured elevation changes; 3 the retreat of the glacier under this
scenario continues with the glacier tongue in a projection to 2030
being situated ≈500 m behind the position in 1977. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|