In situ and airborne observations of sea ice properties are compared to polarimetric C- and X-band synthetic aperture radar images acquired in the Lincoln Sea in 2012 and 2013. A decision-tree classification algorithm is developed to separate level and deformed ice, as well as first- and multi-year ice (MYI), using parameters of the Freeman-Durden Decomposition. Preliminary qualitative and quantitative evaluations of the algorithm indicate it has considerable promise for the separation of these ice types. For the MYI class, correlations between backscatter and ice thickness were moderate to strong for the 2012 field observations but were weak for the 2013 field observations. Further research is required to determine whether or not MYI thickness can be inverted from polarimetric C- and X-band SAR data.