Mathematical morphological analysis of typical cyclone eyes on ocean SAR

Since synthetic aperture radars (SAR) present unique capabilities of measuring the emitted microwave signal response from the sea surface backscatter, they have been widely using in characterizing hurricanes or tropical cyclones. The distinct advantages of ocean SAR imagery enable marine meteorologists to achieve a deeper understanding of catastrophic hurricanes. This study is focused on shape extraction of tropical cyclones (TC) eye areas by introducing mathematical morphology approaches, morphological skeleton and pruning with the aim of ensuring global and local preservation of the precise shape of the eye. These morphological-based analyses are employed explicitly for three representative ocean SAR images with different TC patterns, acquired from Radarsat-1 and Envisat ASAR. The morphological Euclidean skeleton and pruning is based on discrete curve evolution (DCE), resulting in above 92% agreement with the area of coverage derived from reference data.