Structure of southeastern Antarctic Peninsula ice shelves and ice tongues from synthetic aperture radar imagery

Abstract

Examination of synthetic aperture radar data collected over the southeastern Antarctic Peninsula shows that features sometimes mapped as ice shelves are more likely composed of numerous ice tongues interspersed within a matrix of fast ice and icebergs. The tongues are formed by the seaward extension of numerous small mountain glaciers that drain from the Antarctic Peninsula. Once afloat, the tongues intermingle with a matrix of fast ice and brash. Examination of 1997 RADARSAT-1 image mosaics shows that southeastern Antarctic Peninsula composite-ice shelves covered an area of about 3500 km2. Like ice tongues around the rest of Antarctica, these features are highly fragmented and likely to be susceptible to mechanical failure. One such composite shelf, located between New Bedford and Wright Inlets, was observed to decrease in area by 1200 km2 between 1997 and 2000.