Soil-freezing characteristics at the Prudhoe Meadow SoilSCAPE site: (a) comparisons of modeled and observed zero-curtainperiod at two sensor nodes (S5 and S6) using a cutoff threshold of 0.15 (Eq. 12) for both in situ soil dielectric constant and model-simulatedunfrozen water content to determine soil freeze onset; (b) changes in in situ soil dielectric constant during soil freezing at the S6 node. Thesoil dielectric constant was normalized using the maximum and minimum values of soil dielectric constant during the observation period.