A 1976 radio echo sounding expedition to the Vatnajökull ice cap, Iceland

Extract

This brief report describes the first year of a joint Cambridge University—Iceland University two-year project to develop radio echo depth-sounding apparatus suitable for the temperate ice of the Vatnajökull ice cap. There is much interest in obtaining detailed ice thickness measurements for the 8 400 km² Vatnajökull area, where only limited ice-depth surveys, using bore-hole and seismxic techniques, have been carried out in the past. A line of volcanic and geothermal activity extends through the western regions of the ice and creates a sub-glacial lake, Grimsvotn, which collapses every five years or so giving rise to the jökulhlaups, a catastrophic flooding which affects considerable areas of the Icelandic coast to the south of Vatnajökull. Proper understanding of the jökulhlaups phenomena can only be achieved if detailed knowledge of ice thickness and related data are available. Established radio echo sounding techniques which have been successfully applied in the polar regions do not work in water-laden ice such as is to be found in the Vatnajökull area.