Using a draw-wire sensor to continuously monitor glacier melt

Abstract

A draw-wire sensor has successfully been used to measure surface lowering due to net ablation of a glacier. A thin steel wire attached to a weight is inserted and frozen into a borehole in the ice. The draw-wire sensor, installed on a tetrahedron on the surface, retracts the wire as the snow or ice melts. Relative surface lowering of the melting surface is recorded in a data logger and may be converted to mass loss. The instrument continuously logs net ablation over several melt seasons and has the potential to be used extensively in future studies of glacier melt, whenever high temporal resolution and precision are required.