Identification and tracking of individual sea ice floes from ENVISAT wide swath SAR images: a case study from Fram Strait

Abstract

Observations from satellites play an important role in tracking sea ice movement. Synthetic aperture radar (SAR) images are preferred because they are neither weather nor daylight dependent. Tracking the movement of individual objects (icebergs or sea ice floes) that may threaten ships or installations is of particular interest. The Ice Tracking from SAR Images (ITSARI) algorithm was originally developed to track large icebergs in the Antarctic. An adaptation of this algorithm to identify and track the movement of sea ice floes in Arctic conditions is presented, using ENVISAT wide swath SAR images of the Fram Strait acquired at 1–3-day intervals during the month of February 2008. It is shown that the algorithm can be successfully adapted to gain a general sense of the direction of movement of the ice due to both winds and ocean currents and, significantly, to identify and track specific objects of interest over a series of images.

Acknowledgements

This work was supported by a PhD studentship funded by Kongsberg Satellite Services, who also provided the ENVISAT images, courtesy of European Space Agency (ESA). Surface wind vector data were downloaded from http://www.esrl.noaa.gov/psd/data/composites/day/.