Abstract
In the last couple of years many Earth observation satellites with optical instruments have been set in space. These satellites generate an enormous amount of data and give us a image of different landforms on Earth. The data are available for researchers in Earth Science, though efficiently transforming this imagery data to glaciological information has been a challenge. The work in this dissertation presents modern day techniques to extract glacier velocity information from the satellite imagery. Now it is possible to extract reliable displacement measurements from any satellite independent of its flight path. In this way extracting reliable decadal changes of glacier velocity is finally possible. Moreover, by recent development in technology and clever algorithms developed in this PhD work, extracting short term velocity changes are one of the possibilities. So the timing of sliding of a glacier due to melt water can be observed and located. Lastly, methods for data reduction of big data volumes are exploited to develop a discovery tool that is able to observe glacier dynamics over several large mountain ranges. This research might be the first step towards transforming large data volumes into useful information for worldwide glacier monitoring.
List of papers
Paper I: Elevation change and improved velocity retrieval using orthorectified optical satellite data from different orbits. Altena & Kääb. Remote Sensing, 2017, 9, 300; doi:10.3390/rs9030300. The paper is included in the thesis. Also available in DUO: http://urn.nb.no/URN:NBN:no-64035 |
Paper II: Weekly glacier flow estimation from dense satellite time series using adapted optical flow technology. Altena & Kääb. Frontiers in Earth Science, 5:53; doi: 10.3389/feart.2017.00053. The paper is included in the thesis. Also available in DUO: http://urn.nb.no/URN:NBN:no-64034 |
Paper III - Extracting recent short-term glacier velocity evolution over Southern Alaska from a large collection of Landsat data. Altena et al. The Cryosphere Discussions, doi: 10.5194/tc-2018-66, in review, 2018. The paper is included in the thesis. Also available at: https://doi.org/10.5194/tc-2018-66 |