CMG RESEARCH: Boundary Inverse Problems in Glaciology

University Of Alaska Fairbanks Campus, Fairbanks AK

Investigators

Abstract

Truffer ? 0724860 University of Alaska Fairbanks The rate at which glaciers that terminate in the oceans deliver ice to these oceans is an important constraint on predictions of future sea level rise. This rate depends intimately on the basal velocity of the glacier. This velocity cannot be directly measured with the necessary accuracy and spatial resolution to allow accurate estimation of ice mass flux to the oceans. What can be measured is the surface speed of the glacier. The remaining challenge is to use mathematical models to infer basal velocities from the measured surface velocities. This problem has no straightforward mathematical solution. Techniques known as inverse methods, which are not yet fully understood from a mathematical standpoint, must be used. Funds are provided to develop, test and apply rigorous inverse methods to the problem of finding basal velocity fields under glaciers and ice sheets. The work supported here will explore a set of problems based on nonlinear, isothermal, incompressible ice flow. The goals are to develop methods useful for glaciology, or geophysics in general, and at the same time derive some basic mathematical results about these methods.