Using an ultra-long-range terrestrial laser scanner to monitor the net mass balance of Urumqi Glacier No. 1, eastern Tien Shan, China, at the monthly scale

• Published in: Journal of Glaciology
• Main Authors: CHUNHAI XU, ZHONGQIN LI, FEITENG WANG, HUILIN LI, WENBIN WANG, LIN WANG
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2017
• Subjects: glacier area; glacier surface elevation changes; monthly scale; net mass balance; Riegl VZ®-6000 terrestrial laser scanner; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; Journal of Glaciology
• Online Access: https://doi.org/10.1017/jog.2017.45; https://doaj.org/article/c4de255e8ec4424c86c3c84a73bb5624

We describe the use of a terrestrial laser scanner (TLS) to monitor the net mass balance of Urumqi Glacier No. 1, eastern Tien Shan. We used an ultra-long-range Riegl VZ®-6000 TLS, which is specially designed for surveying snow- and ice-covered terrain, to create repeated high spatiotemporal resolution DEMs, focusing on the monthly-scale (25 April–28 May 2015) net mass balance. According to the TLS-derived DEMs, the area of Urumqi Glacier No. 1 was 1.558 km2 on 25 April 2015 and the average surface elevation change was 0.225 m. By comparing the results from the use of TLS with the conventional glaciological mass-balance method, the correlation coefficient (R 2) between glaciological elevation changes of individual stakes and the TLS-derived geodetic elevation change of corresponding points was 0.85. Considering the uncertainty of both methods, this is a promising result. Using the in situ measured snow densities (snow pits) of the glacier surface, the geodetic net mass balance was 0.074 m w.e., which is slightly positive. The mean uncertainty in the TLS-derived monthly net mass balance was 0.018 m w.e., showing that the TLS surveying system presented accurate and relevant results and is therefore suitable to monitor mass-balance evolution of mountain glaciers.