Initiation of a major calving event on the Bowdoin Glacier captured by UAV photogrammetry
OPEN ACCESS
Loading...
Author / Producer
Date
2017-04-12
Publication Type
Journal Article
ETH Bibliography
yes
Citations
Altmetric
OPEN ACCESS
Data
Rights / License
Abstract
In this paper, we analyse the calving activity of the Bowdoin Glacier, north-western Greenland, in 2015 by combining satellite images, UAV (unmanned aerial vehicle) photogrammetry and ice flow modelling. In particular, a high-resolution displacement field is inferred from UAV orthoimages taken immediately before and after the initiation of a large fracture, which induced a major calving event. A detailed analysis of the strain rate field allows us to accurately map the path taken by the opening crack. Modelling results reveal (i) that the crack was more than half-thickness deep, filled with water and getting irreversibly deeper when it was captured by the UAV and (ii) that the crack initiated in an area of high horizontal shear caused by a local basal bump immediately behind the current calving front. The asymmetry of the bed at the front explains the systematic calving pattern observed in May and July–August 2015. As a corollary, we infer that the calving front of the Bowdoin Glacier is currently stabilized by this bedrock bump and might enter into an unstable mode and retreat rapidly if the glacier keeps thinning in the coming years. Beyond this outcome, our study demonstrates that the combination of UAV photogrammetry and ice flow modelling is a promising tool to horizontally and vertically track the propagation of fractures responsible for large calving events.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
11 (2)
Pages / Article No.
911 - 921
Publisher
Copernicus
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Organisational unit
Notes
Funding
Related publications and datasets
Is new version of: