Studies of Antarctic Sea Ice Characteristics Using Surface Sea Ice Measurements and TerraSAR-X Data

Due to its great extent in winter and retreat in summer, sea ice in the Southern Ocean has a great influence on regional and global energy balances. Satellite radar data provide high-resolution, all-time (day/night) and all-weather images of the mostly cloud-covered Southern Ocean. In this study, TerraSAR-X (TSX) dual-pol observations are analyzed to determine the sea ice characteristics of the Bellingshausen and Amundsen Sea in the Antarctic region. Surface sea ice characteristics are derived from ship-based sea ice observations and sea ice measurement stations during the J.C. Ross 2010 (IceBell) and Oden 2010-11 expeditions during the austral summer (i.e., late October 2010 to January 2011). Data from ice mass-balance buoys emplaced during the two cruises continued through summer melt and bridged the transition into fall freeze up conditions in the snow pack and ice cover. Previous results (C-band backscatter) suggest that the X-Band of TSX is sensitive to snow and ice properties, and the presence of wet snow and age/temperature of summer snow pack. Relationships between the different ice types and snow or ice-surface properties and the radar backscatter response are examined regarding their potential to improve satellite applications to sea ice characterization, particularly as backscatter evolves in correspondence with temperatures and changing surface conditions through the summer and into the fall freeze up period.