SEASONAL COMPARISON OF VELOCITY OF THE EASTERN TRIBUTARY GLACIERS, AMERY ICE SHELF, ANTARCTICA, USING SAR OFFSET TRACKING

• Published in: ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
• Main Authors: S. D. Jawak, S. Kumar, A. J. Luis, P. H. Pandit, S. F. Wankhede, T. S. Anirudh
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2019
• Subjects: Technology; T; Engineering (General). Civil engineering (General); TA1-2040; Applied optics. Photonics; TA1501-1820; Antarctic; The Antarctic; East Antarctica; Prydz Bay; Greenland; Amery; Amery Ice Shelf; Clemence Massif; American Highland; Pickering Nunatak; Antarc*; Antarctica; glacier; Ice Sheet; Ice Shelf; Ice Shelves
• Online Access: https://doi.org/10.5194/isprs-annals-IV-2-W5-595-2019; https://doaj.org/article/ac4dec7a9af64d669dcbc53c4193f67f

Antarctica and Greenland are two major Earth’s continental ice shelves which play an important role in influencing Earth’s energy balance through their high albedo. The ice sheets comprise of grounded ice or the continental glaciers and their associated ice shelves. Surface velocity is an important parameter that needs to be monitored to understand the glacier dynamics. Marine terminating glaciers have higher velocity than land terminating glaciers. Therefore, ice shelves are generally observed to have higher velocity as compared to continental glaciers. The focus of this study is Amery ice shelf (AIS) which is the third largest ice shelf located in east Antarctica terminating into the Prydz Bay on the eastern Antarctica. The surface ice-flow velocity of AIS is very high compared to its surrounding glaciers which flows at a rate of 1400 m a −1 and drains about 8% of the Antarctic ice sheet. AIS is fed by different glaciers and ice streams at the head, as well as from the western and eastern side of the ice shelf before it terminates into the ocean. The primary objective of this study was to compute velocity of the eastern tributary glaciers of AIS using SAR from Sentinel-1 data. The secondary objective was to compare the winter and summer velocities of the glaciers for 2017–2018. The offset tracking method has been applied to the ground range detected (GRD) product obtained from Sentinel-1 satellite. This method is suitable for regions with higher glacier velocity where interferometry is generally affected by the loss of coherence. The offset tracking method works by tracking the features on the basis of another feature and calculates the offset between the two features in the images. Two tributary glaciers near the Clemence massif and another glacier near the Pickering Nunatak feed into this ice shelf from the eastern glacial basin region that drains ice from the American Highland, east Antarctica. The glaciers near the Clemence massif showed low annual velocity which ranged from 100 m a −1 at the head to ∼300 ...