Ocean Tide Modeling in South Ross Sea Using Interferometric SAR and Radar Altimetry

Ohio State University Research Foundation -Do Not Use, Columbus OH

Investigators

Abstract

0088029 Shum The proposed work is an attempt to use radar altimeter data and synthetic aperture radar data in an interferometric mode from ERS-1 and ERS-2 to develop a barotropic model of the ocean tide under the Ross Ice Shelf. A 30-kilometer resolution model will be applied to the entire Ross Ice Shelf, while a higher resolution (30 meters) model will be developed for a 100 square kilometer section of the shelf edge. One expected result of this work is an improved location of the southern grounding line of the Ross Ice Shelf. Ocean tides play a significant role in the complex interactions between the atmosphere, ocean, sea ice and floating glacial ice shelves. Tidal currents creates turbulent mixing at the bottom of the ice shelf contributing to the creation of rifts for the possible detachment of part of the icebergs and can influence heat transport between the ice shelf and sea water. The primary scientific objectives of the proposed investigation include: (1) the development of methodologies to diminish the tidal aliasing limitations and to use repeat-pass synthetic aperture radar interferometry (InSAR) and radar altimeter data from ERS-1 and ERS-2 for the determination of a fine resolution (30-50 m) barotropic ocean tide model in the South Ross Sea region, (2) a coarser resolution (30 km) barotropic ocean tide model covering the floating ice shelf region of the Ross Ice Shelf, (3) the assessment and quantification of errors associated with the resulting tide model, and (4) provide a demonstration of improved determination of grounding line between grounded ice and ice shelf in the South Ross Sea. The approach will make use of the convergence of ERS ground tracks over the southern Ross Sea and the overlapping of SAR swaths to attempt to break the tidal aliasing. The resulting model will be validated for its accuracy and applied to a test case of its potential improvement in the detection of grounding lines in the South Ross Sea Ice Shelf. ***