Ferran Hernández-Macià, Carolina Gabarro, Marcus Huntemann, Reza Naderpour, Joel T. Johnson, Ken C. Jezek

The sea ice thickness retrieval using L-band passive remote sensing requires robust sea ice emission models. In this work, measurements from surface-based radiometers during MOSAiC are assessed with the Burke, Wilheit and SMRT models. These models encompass three distinct methodologies: incoherent without scattering, incoherent with scattering, and coherent approaches. Before running them, the sea ice growth is simulated using the CFDD model to further compute the evolution during each period. Ice cores near the instruments are used as initial state of the computation, along with DTC data to derive the sea ice temperature. The results suggest that the coherent approach used in the Wilheit model results in a better agreement with the horizontal polarization of the in situ measured brightness temperature. The Burke and SMRT incoherent models offer a more robust fit for the vertical component. These models are almost equivalent since the scattering considered in SMRT can be safely neglected at this low frequency, but the Burke model misses an important contribution from the snow layer above sea ice. The results also suggest that a more realistic permittivity falls between the spheres and random needles formulations, with potential for refinement, particularly for L-band applications, through future field measurements.