Icebergs in Sea Ice With TanDEM-X Interferometry

In this paper, the advantages of using an interferometric method for detecting and characterizing icebergs in sea ice were demonstrated. Iceberg topography was analyzed using single-pass TanDEM-X interferometric synthetic aperture radar (InSAR) data. Multiple InSAR data sets in bistatic mode were acquired over icebergs in sea ice in the Arctic region. InSAR processing was used to extract 3-D elevation information of the sea ice surface. The results firmly demonstrate the capability of TanDEM-X data to characterize the shape of icebergs. Very high resolution (VHR) optical satellite data were collected by Pleiades 1A over the same area to derive digital elevation models (DEMs) of ice features for validation. The accuracy of the extracted topography over icebergs was evaluated by comparing InSAR and optical DEMs. The quantitative comparison demonstrated good correspondence between InSAR and optical DEMs with root-mean-square value values of 2.2 m for icebergs and 0.6 m for sea ice, respectively. Using DEMs derived from VHR optical imagery, it was possible to calculate receiver operating characteristics (ROC) for detecting icebergs in sea using InSAR. The resulting ROC analysis illustrates a good detection performance.