M. Schäfer, O. Gagliardini, E. Le Meur, F. Pattyn, C. Ritz schaefer

to the HO/FS one when the surface gets closer to a steady state. There is a better ... 8 zoom, same as Fig.7, dependency on the bedrock slope. Fig. 4 initial ...
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Mountain glacier flow modelling : a comparison of different models from the Shallow Ice Approximation to the Full-Stokes solution

M. Schäfer, O. Gagliardini, E. Le Meur, F. Pattyn, C. Ritz

Glacier Flow modelling inverse model

velocity profile

q2

MB (climate)

sliding

sliding law T,, ...

ice flow

To calculate the ice thickness rate of change at each point of the glacier, mass balance data and velocity field are necessary. The velocity field is driven by the force budget (Stokes equations ), a flow law (Glen with n=3), a sliding law (Weertman type) and boundary conditions.

model parameters

flow law

Cotopaxi

Objectives

Saint Sorlin

The objective of the present study is to estimate wich is the most appropriate type of model to use given the specificity of the glacier to model. Respective effects on glacier dynamics of deformation, sliding and mass balance are separatey addressed.

Argentière

Fig. 1

Spherical glacier

spherical glacier

zoom

Fig. 3 same as Fig. 2, effect of MB

geometry after 50years, no MB, slope 0.3

without MB with MB ......

to

Fig. 4

Le Meur and Vincent, 2003

SIA, 0th order

F SIA

Pattyn, 2003

SIA, 0th order

F HO

Pattyn, 2003

Higher Order Hydrostatic approximation dw/dx,y