This dataset was collected during a controlled sea ice growth experiment at the Sea-ice Environmental Research Facility (SERF), University of Manitoba, Winnipeg, Canada, in Winter 2020. Over a 4-day experiment, the experiment had two phases. In phase 1, pure ice was grown from open water to about 5 cm of ice, while in phase 2, oil-contaminated ice was grown up to thickness of 5 cm. The dataset captures 6 radar and environmental parameters relevant to sea ice formation and structure, including C-band polarimetric radar backscatter (VV, HH, HV) at a 25° incidence angle, air temperature, cumulative freezing degree moments (CFDM), and ice thickness. Radar data were collected using a C-band scatterometer operating at 5.5 GHz with 30° azimuth swaths. This multivariate time series dataset is suitable for research in sea ice thickness modeling, remote sensing, and environmental monitoring.