Assessing the applicability of terrestrial laser scanning for mapping englacial conduits.

• Published in: Journal of Glaciology
• Main Authors: Kamintzis, J.E., Jones, J. P. P., Irvine-Fynn, T. D. L., Holt, T. O., Bunting, P., Jennings, S. J. A., Porter, Philip, Hubbard, B.
• Other Authors: Agriculture, Food and Veterinary Sciences, Geography, Environment and Agriculture, Water and Environment, Department of Biological and Environmental Sciences, School of Life and Medical Sciences, Agriculture and Environmental Management Research
• Language: English
• Published: 2018
• Subjects: arctic glaciology; glacier mapping; glaciological instruments and methods; remote sensing; Earth-Surface Processes; Arctic; Svalbard; Teardrop; glacier; Journal of Glaciology
• Online Access: http://hdl.handle.net/2299/19988; http://www.scopus.com/inward/record.url?scp=85042232147&partnerID=8YFLogxK

his is an Open Access article, distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike licence (http://creativecommons.org/licenses/by-nc-sa/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the same Creative Commons licence is included and the original work is properly cited. The written permission of Cambridge University Press must be obtained for commercial re-use. The morphology of englacial drainage networks and their temporal evolution are poorly characterised, particularly within cold ice masses. At present, direct observations of englacial channels are restricted in both spatial and temporal resolution. Through novel use of a terrestrial laser scanning (TLS) system, the interior geometry of an englacial channel in Austre Brøggerbreen, Svalbard, was reconstructed and mapped. Twenty-eight laser scan surveys were conducted in March 2016, capturing the glacier surface around a moulin entrance and the uppermost 122 m reach of the adjoining conduit. The resulting point clouds provide detailed 3-D visualisation of the channel with point accuracy of 6.54 mm, despite low (<60%) overall laser returns as a result of the physical and optical properties of the clean ice, snow, hoar frost and sediment surfaces forming the conduit interior. These point clouds are used to map the conduit morphology, enabling extraction of millimetre-to-centimetre scale geometric measurements. The conduit meanders at a depth of 48 m, with a sinuosity of 2.7, exhibiting teardrop shaped cross-section morphology. This improvement upon traditional surveying techniques demonstrates the potential of TLS as an investigative tool to elucidate the nature of glacier hydrological networks, through reconstruction of channel geometry and wall composition. Peer reviewed Final Published version