Mass And Thermal Flow In Glaciers
Free (open access)
L De Biase & A Deponti
Glaciers play a fundamental role in the study of pollution and climate changing; from ice cores it is in fact possible to track the evolution of chemical and physical properties of the atmosphere over different scales of time and space. A temperature vs. depth profile is required for drilling operations while an age vs. depth profile is required for data interpretation. Such information comes from the knowledge of the thermo-dynamics of the glacier under study and thus, from a good mathematical flow model. Ice thermo-dynamics is non-linear and convection dominated. Both these characteristics represent the major tasks to be faced during the formulation of a numerical model. A number of models have been proposed before, but none seems to be efficient enough to model a section of complex geometry such as sections of Alpine glaciers. The mass-flow model proposed in this work is based on the assumptions that the pressure is lithostatic throughout the domain and that stress and velocity are twice differentiable vector functions. Under these assumptions i t is possible to split the entire system into smaller and simpler systems and to double derive the equations in such a way that second order terms are obtained. The velocity field obtained is the input for computing the heat transfer equation. All the systems are solved by the Finite Difference Method using a regular but non-uniformgrid.