Validation of the basal stress boundary utilizing Satellite Imagery along the George VI Ice Shelf, Antarctica

Mentor: Michael Jefferson, Eliazabeth City State University

Keywords: ENVI, GloVis, Natural Basal Stress Boundary, ASAID Basal Stress Boundary, Landsat, Ice Shelf, Ice Sheet

Abstract
Majority of ice shelves are fed by inland glaciers. Together, an ice shelf and the glaciers feeding it can form a stable system, with the forces of outflow and backpressure balanced. Warmer temperatures can destabilize this system by increasing glacier flow speed and more dramatically by disintegrating the ice shelf. Without a shelf to slow its speed, the glacier accelerates. After the 2002 Larsen B Ice Shelf disintegration, nearby glaciers in the Antarctic Peninsula accelerated up to eight times their original speed over the next 18 months. Similar losses of ice tongues in Greenland have caused speed-ups of two to three times the flow rate in just one year.

Rapid changes occurring in regions surrounding Antarctica are causing concern in the polar science community to research changes occurring in coastal zones over time. During the research, the team completed a study on George VI Ice Shelf located on the western coast of the Antarctic Peninsula. The study included a validation of the Antarctic Snow and Ice Accumulation Discharge Basal Stress Boundary (ABSB) vs. the natural basal stress boundary (NBSB) along the George VI Ice Shelf. The ASAID BSB was created by a team of researchers headed by National Aeronautics and Space Administration Goddard Space Flight Center (NASA GSFC), with an aim of studying coastal deviations as it pertains to the mass balance of the entire continent. The point data file was aimed at creating a replica of the natural BSB. Select cloud free Landsat satellite imagery from satellites 1 through 7 was used to detect changes occurring over the span of 19 years. The last major interest in the study included documenting the deviations or incorrect placements of the ABSB vs NBSB. Changes that occurred were documented in the form of a table with the change that occurred along with the geographic coordinates.