Interpretation of C-band SAR backscattering coefficient time series for the Baltic Sea landfast sea ice using a 1-D thermodynamic snow/ice model

We have compared time series of C-band HH-polarization backscattering coefficients (sigmadeg ) of the Baltic Sea land-fast level ice with results from a 1D high-resolution thermodynamic snow/ice model (HIGHTSI). The sigmadeg time series were obtained from ENVISAT synthetic aperture radar (SAR) images acquired in February 3 - April 7, 2004, and February 6 - April 30, 2006. Typically the HIGHTSI results greatly helped to interpret the sigmadeg behavior with changing weather conditions. There were some cases where detailed ground truth, combined with theoretical sigmadeg modeling, would have been needed for interpretation of the sigmadeg trends. From the point of view of operational Baltic Sea ice monitoring with SAR images, the most interesting observation was the large variation of level ice sigmadeg with changing weather conditions.