Sökning: "glacier modeling"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden glacier modeling.

1. 1. Stability of the free-surface problem arising in ice-sheet- and glacier modeling : Numerical investigation and stabilization

   Författare :André Löfgren; Josefin Ahlkrona; Fabien Gillet-Chaulet; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ice-sheet modeling; glacier modeling; ice-sheet dynamics; free-surface flow; stability; stabilization; free-surface stabilization algorithm; Numerical Analysis; numerisk analys;

   Sammanfattning : This thesis consists of two papers dealing with a stabilization method for free-surface flows. The method was initially developed to stabilize mantle-convection simulations, but is in this work extended to ice-sheet- and glacier modeling. LÄS MER

3. 2. Force Budget Analysis of Glacier Flow : Ice Dynamical Studies on Storglaciären, Sweden, and Ice Flow Investigations of Outlet Glaciers in Dronning Maud Land, Antarctica

   Författare :Jim Hedfors; Veijo Pohjola; Else Kolstrup; Niels Reeh; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical geography and sedimentology; force budget; ice flux; ice dynamics; mass balance; strain heating; climate change; Storglaciären; Dronning Maud Land; Antarctica; Naturgeografi och sedimentologi; Physical geography; Naturgeografi;

   Sammanfattning : This thesis contributes to the understanding of glacier response to climate change by ice dynamical studies on Storglaciären, Sweden, and Bonnevie-Svendsenbreen, Kibergbreen and Plogbreen in Dronning Maud Land, Antarctica. Ice surface velocities, ice geometry and temperature information is fed through a force budget model to calculate ice mass outflux of these glacial systems via three-dimensional stress distributions for a flux-gate. LÄS MER

4. 3. Dynamics of the cold surface layer of polythermal Storglaciären, Sweden

   Författare :Rickard Pettersson; Per Holmlund; Peter Janssson; Jens-Ove Näslund; Regine Hock; Helgi Björnsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polythermal glacier; cold surface layer; ground-penetrating radar; spatial variability; water content; Storglaciären; Earth sciences; Geovetenskap;

   Sammanfattning : Polythermal glaciers, i.e. glaciers with a combination of ice at and below the freezing point, are widespread in arctic and subarctic environments. The polythermal structure has major implications for glacier hydrology, ice flow and glacial erosion. LÄS MER

5. 4. Glacial Isostatic Adjustment : Inferences on properties and processes in the upper mantle from 3D dynamical modeling

   Författare :Peter Schmidt; Björn Lund; Christoph Hieronymus; Laust Pedersen; Zdenek Martinec; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Observations of glacial isostatic adjustment (GIA) offers a powerful window into the properties of the Earth's interior. Combined with dynamical modeling of the GIA process we can use the observations to infer properties such as the elastic structure of the lithosphere, the rheology of the mantle and changes in the stress conditions in the Earth. LÄS MER

7. 5. Basal boundary conditions, stability and verification in glaciological numerical models

   Författare :Christian Helanow; Peter Jansson; Brian Hanson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Glaciology; subglacial hydrology; ice sheet modeling; basal boundary conditions; non-linear Stokes flow; Physical Geography; naturgeografi;

   Sammanfattning : To increase our understanding of how ice sheets and glaciers interact with the climate system, numerical models have become an indispensable tool. However, the complexity of these systems and the natural limitation in computational power is reflected in the simplifications of the represented processes and the spatial and temporal resolution of the models. LÄS MER