C-band backscattering signatures of Baltic Sea ice

A large data set of backscattering signatures of different Baltic Sea ice types have been acquired with an helicopter-borne C- and X-band scatterometer (HUTSCAT). In this study C-band moist snowcover and bare dry ice data sets were used. The variation of the mean /spl sigma//sup /spl deg// at HH-polarization between the incidence angles of 23 and 45 degrees was the largest for open water leads and smooth level ice and the smallest for heavily deformed ice and frozen brash ice. Std of texture depends on polarization, incidence angle, ice type and snow cover category. At co-polarizations mean Stds are roughly equal. The contrast between level ice and ridge /spl sigma//sup /spl deg// is larger at cross polarization than at co-polarizations. The small difference between /spl sigma//sup /spl deg// at VV- and VH-polarization for ridges suggest that the main scattering mechanism in ridges is multiple scattering between the ice blocks or multiple surface scattering.