It is proposed that a radio altimeter be installed in a satellite to measure its height above the surface. It should work at a frequency of the order of 104 Mc/s and measure heights to an accuracy as close as practicable to ± 5 m. Heights above the ocean would be extrapolated to calculate satellite heights above sea level while over the Antarctic continent, and the difference between this calculated height and the measured height would give the surface elevation. Geometrical sounding errors and systematic errors may cause errors up to 50 m on relatively flat ice sheets, but incremental errors over 10 km should be of the order of 10 m. The systematic coverage of the Antarctic continent by a few weeks' observations from a satellite should make a detailed contour map practicable. The system would not be satisfactory for the peripheral areas where many slopes exceed 1:200 and are less regular than elsewhere, but these areas are being surveyed by conventional methods.

You do not currently have access to this article.