A study of new-ice formation, using Cosmo-SkyMed (CSK) SAR imagery, was planned for the period February - March, 2015 over Terra Nova Bay (Antarctica). The first survey of the images showed an unexpected surface feature, i.e., a prominent ice gyre which lasted from the image of 20 February to the one of 12 March; in the image of 17 March, the ice gyre appears already completely disrupted and a well-defined polynya comes into sight. The analysis of the gyre extent in the image sequence became the object of our study. The non-linear segmentation of the set of CSK images was performed by the perceptron algorithm; this is a significant challenge because of the random nature of the speckle degradation in SAR images. The final result is a set of binary patterns providing the gyre area of each image; by this it is possible to follow the time evolution of the particular feature.
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