Articles | Volume 11, issue 4
Research article
29 Aug 2017
Research article |  | 29 Aug 2017

Sea ice local surface topography from single-pass satellite InSAR measurements: a feasibility study

Wolfgang Dierking, Oliver Lang, and Thomas Busche

Abstract. Quantitative parameters characterizing the sea ice surface topography are needed in geophysical investigations such as studies on atmosphere–ice interactions or sea ice mechanics. Recently, the use of space-borne single-pass interferometric synthetic aperture radar (InSAR) for retrieving the ice surface topography has attracted notice among geophysicists. In this paper the potential of InSAR measurements is examined for several satellite configurations and radar frequencies, considering statistics of heights and widths of ice ridges as well as possible magnitudes of ice drift. It is shown that, theoretically, surface height variations can be retrieved with relative errors  ≤  0.5 m. In practice, however, the sea ice drift and open water leads may contribute significantly to the measured interferometric phase. Another essential factor is the dependence of the achievable interferometric baseline on the satellite orbit configurations. Possibilities to assess the influence of different factors on the measurement accuracy are demonstrated: signal-to-noise ratio, presence of a snow layer, and the penetration depth into the ice. Practical examples of sea surface height retrievals from bistatic SAR images collected during the TanDEM-X Science Phase are presented.

Short summary
Information on the sea ice surface topography is valuable in geophysical investigations such as studies on atmosphere–sea ice interactions or sea ice mechanics. We investigated whether space-borne radar systems can be used to measure sea ice elevation. The answer is yes, but disturbing effects have to be considered, in particular sea ice drift and certain technical constraints. With future satellite radar missions, a fast wide-coverage acquisition of sea ice topography may be possible.