Observations of sea-ice conditions in the Antarctic coastal region using ship-board video cameras

Abstract

During the 30th, 31st, and 32nd Japanese Antarctic Research Expeditions (JARE-30,JARE-31,and JARE-32), sea-ice conditions were recorded by video camera on board the SHIRASE. Then, the sea-ice images were used to estimate compactness and thickness quantitatively. Analyzed legs are those toward Breid Bay and from Breid Bay to Syowa Station during JARE-30 and JARE-31,and those toward the Prince Olav Coast, from the Prince Olav Coast to Breid Bay, and from Breid Bay to Syowa Station during JARE-32. The results show yearly variations of ice compactness and thickness, latitudinal variations of thickness, and differences in thickness histograms between JARE-30 and JARE-32 in Lutzow-Holm Bay. Albedo values were measured simultaneously by a shortwave radiometer. These values are proportional to those of ice compactness. Finally, we examined the relationship between ice compactness and vertical gradient of air temperature above sea ice.