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Polarization of radio waves in ice sheets
No full textThe polarization behaviour of radio waves which have been transmitted and reflected at or near normal incidence in an ice sheet can be explained if the ice is assumed to be a uniaxial birefringent material. Equations are derived for describing the change in polarization for the experimental conditions usually encountered when sounding ice sheets. One of the initial unknowns which can be found is the direction of the effective optic axis which determines the basic reference frame. Other parameters which can be found and related to the physical nature of the ice and reflecting surface are the total phase shift between the ordinary and extraordinary rays and their relative amplitude. The operation of several different types of polarimeter is discussed in order to compare the amount and the quality of information which can be obtained for various degrees of complexity in equipment and technique
Antarctic mass balance: glaciological evidence from Antarctic Peninsula and Weddell Sea sector
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Thermodynamics of the interaction between ice shelves and the sea
No full textAn ice shelf is a floating ice sheet, attached to land where ice is grounded along the coastline. Nourished both by surface snow accumulation and by glaciers and ice sheets flowing off the land, ice shelves can reach a considerable thickness, varying from up to 1 300 m when the ice starts to float to 200 m or less at the seaward edge (known as the ice front). Nearly all the world's ice shelves are found in Antarctica, where they cover an area of about one and a half million square kilometres. The two largest are the Ross Ice Shelf and the Filchner-Ronne ice shelf, each with an area of about half a million square kilometres. Smaller ice shelves fringe other parts of the Antarctic coastline
Sea-bed depths at the mouth of Rutford Ice Stream, Antarctica
No full textSeismic measurements of ice- and water column thickness have been made on Rudard Ice Stream where it joins the Ronne Ice Shelf. Assuming that the ice is in hydrostatic equilibrium, these values have been used to calculate sea-bed elevations. A sea-bed trough more than 2 km below sea level along the western margin continues downstream from the grounded to the floating ic
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