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Pine Island Glacier (Antarctica) velocities from Landsat7 images between 2001 and 2011: FFT-based image correlation for images with data gaps
journal contribution
posted on 2023-05-17, 20:00 authored by Roland WarnerRoland Warner, Jason RobertsJason RobertsRemote sensing of ice motion by tracking displacement of surface features is a valuable tool in glaciology. Efficient image feature-tracking programs, such as IMCORR, based on fast Fourier transform methods can produce misleading correlations if there are data gaps in either or both of the reference and search images. This is particularly problematic if the data gaps are regular in character, such as for Landsat7 images collected after the failure of the Scan Line Corrector (SLC-off images). We demonstrate that this situation can be alleviated by filling the data gaps with suitably chosen random data. We modified IMCORR to achieve this automatically (source code is included), but generic image-processing software could be used to modify inputs for other correlation packages. We test our method using images of Pine Island Ice Shelf, Antarctica, and document the acceleration of the velocity field for the floating extension of Pine Island Glacier over the decade 2001–11. We also combine our velocities with recent NASA Operation IceBridge ice thickness data from CReSIS to estimate the basal melt rates.
History
Publication title
Journal of GlaciologyVolume
59Issue
215Pagination
571-582ISSN
0022-1430Department/School
Institute for Marine and Antarctic StudiesPublisher
Int Glaciol SocPlace of publication
Lensfield Rd, Cambridge, England, Cb2 1ErRights statement
Copyright 2013 IGSRepository Status
- Restricted