Detection of glaciers displacement time-series using SAR

EULLIADES, L.; EULLIADES, P. ; RIVEROS, N. ; MASIOKAS, M.; RUIZ L.; PITTE, P.; ELEFANTE, S.; CASU, F. ; BALBARINI, S.

REMOTE SENSING OF ENVIRONMENT

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2016 p. 188 - 198

0034-4257

Glaciersare sensitive indicators of climate change. Particularly, glacier surfacevelocity constitutes a key parameter for estimating ice volume variations asresponse to global warming and its incidence in sea level rise. Several methodologiesbased in remotely sensed data have been employed for estimating ice velocityfields. They are mostly based in cross-correlating pairs of images in order totrack features displacement between two dates. High ice flux velocity, whichcan reach more than 1 km/year, constitute a challenge for the existingmethodologies, in practice limiting to a fewdays the time span between usefuldata. In thiswork we present an extension of the known Pixel Offset ? SmallBaseline Subsets (PO-SBAS) technique, that profit a set of successive SyntheticAperture Radar (SAR) scenes for computing displacement time series and icevelocity fields. The algorithm is guided by a preliminary ice velocity modelestimated from the data itself, which significantly improves the resultsreliability and reduces the overall computational cost. Furthermore, itimplements a processing scheme that considers the displacement estimations (PO)quality in order to decide which pixels are included in the time series inversion.The proposed technique is applied to 22 COSMO-Skymed SAR images of ViedmaGlacier (Southern Patagonian Icefield, Argentina) spanning roughly a year. Theresults obtained are robust and make profit of the whole available dataset.Resulting mean velocity field and displacement time series show the algorithm suitabilityfor retrieving and characterizing complex ice motion patterns.