Ice Dynamics at Dome C, East Antarctica

The University Archives has determined that this item is of continuing value to OSU's history.The temperature distribution in an ice sheet depends on the advective transport of heat in the ice as well as the nature of the boundary conditions at the upper and lower surfaces. This fact is exploited here in an analysis of an 800 meter temperature profile measured at Dome C, East Antarctica. An ice sheet model is outlined for which the heat equation is solved numerically. Surface boundary conditions are specified in terms of an interpretation of the Dome C oxygen isotope profile, while basal conditions are related to radio-echo sounding data. Two different classes of functions are considered for the longitudinal strain rate, both consisting of simple polynomials that can be characterized by a single parameter. Temperature profile s generated by each function are compared with the measured profile. For the boundary conditions assumed here, the best fit results from a strain rate function proportional to (l-z/H)P, with H the ice thickness and p approximately 2.5. As a result, the vertical velocity decreases rapidly with depth in the upper half of the ice sheet. The corresponding depth-age relation suggests that ice at 1400 m depth could be as old as 80,000 to 90,000 years.National Science Foundation Grant DPP-7823834