Publisert 06.03.2019 , sist oppdatert 27.05.2019

Glacier velocity

Background

Satellite imagery, with its repeated acquisition, and global coverage, represents a unique opportunity to quantify spatial and temporal changes in dynamics of mountain glaciers and ice caps (Dehecq et al., 2015). The ability to process a large amount of satellite imagery efficiently, and retrieve time series of ice displacement is key for understanding past, present, and future changes in ice dynamics. Velocity measurements of glaciers can be determined by using image matching of repeated optical imagery. It is possible to map glacier velocity sub-seasonally, and more accurately than earlier due to the higher spatial and temporal resolution of Sentinel-2 satellite images (Kääb et al., 2016).

Data glaciers mainland Norway

NVE has started to map surface velocity using optical imagery from Sentinel-2 for a selection of glaciers in Norway. Sentinel-2A and Sentinel-2B imagery were used for establishing pairs for feature tracking. The SenDiT toolbox that incorporates IMCORR feature tracking software was used to calculate displacement fields. Resulting displacement fields were manually filtered taking into account expected magnitude and direction of movement. This first dataset gives velocity data for Nigardsbreen, Tunsbegdalsbreen, Engabreen and Rembesdalskåka.

Download velocity data as a zipped file:

NVE 2019. Glacier velocity data. version 1.0. Copernicus Glacier Service/Copernicus bretjeneste. Norwegian Water Resources and Energy Directorate, Oslo, Norway.

SenDiT toolbox

Here you can download SenDiT (Sentinel-2 Displacement Toolbox) with application to glacier surface velocities. If you use the toolbox for research or other purposes, please cite Nagy et al. (2019) in any publications. Please refer to License.txt file for full reference and license details. To start with the toolbox, please follow instructions in the 00_readme.txt file. Download SenDiT

SenDiT is a semi-automatic, open-source, flexible processing toolbox for retrieval of displacement maps with application to obtaining glacier surface velocities. SenDiT combines the download, pre-processing, feature tracking, and postprocessing of highest resolution Sentinel-2A and Sentinel-2B satellite images into a semi-automatic toolbox, leaving a user with a set of rasterized and georeferenced glacier flow magnitude and direction maps for further analyses. The solution is freely available and is tailored so that non-glaciologists and people with limited GIS knowledge can also benefit from it.

SenDiT is developed by Teodor Nagy. Contact teon'at'nve.no with any questions on the tool functionality.

References

Dehecq, A., Gourmelen, N., Trouve, E. 2015. Deriving large-scale glacier velocities from a complete satellite archive: application to the Pamir–Karakoram–Himalaya. Remote Sens. Environ. 2015, 162, 55-66.

Kääb, A., Winsvold, S. H., Altena, B., Nuth, C., Nagler, T. and Wuite, J. 2016. Glacier Remote Sensing Using Sentinel-2. Part I: Radiometric and Geometric Performance, and Application to Ice Velocity. Remote Sensing, 8(7), 598. (pdf)

Nagy, T., Andreassen, L. M., Duller, R. A. and Gonzalez, P. J. 2019. SenDiT: A Sentinel-2 Displacement Toolbox with application to glacier surface velocities. Remote Sensing, 11, 1151. (pdf)