Monitoring of Blue-Ice Extent on Satellite Images of Grove Mountains, Antarctica

This report presents the finding of seasonal and interannual variations of blue-ice extent in the Grove Mountains, by using images from Moderate Resolution Imaging Spectroradiomete (MODIS) and Landsat. The MODIS raw data were first treated by the pretreatment methods and the blue-ice pixels was separated by the blue-ice mapping algorithm. From the data over three summer seasons, the variation regularity of seasonal blue-ice exposure are summarized. The area grows rapidly from September to December and peaks to about 600km(2) by the middle or late of next January, then it declines from February to April. The Landsat images were then processed by supervised classification combining with visual revision. According to the result images over 30 years, the margins of blue-ice feature were compared and the eastward trend of blue-ice extent can be concluded. Besides, the combination of MODIS and Landsat data indicates that the seasonal variation is more obvious than the interannual changes for the Grove blue ice, and the blue-ice areas are sensitive to the change of climate and shortwave radialization.