Yackel, John J.Nanda Kumar Sreeletha, Vishnu Nandan2024-10-292018-08-212024-10-292018-08-20Nanda Kumar Sreeletha, V. N. (2018). Multi-Frequency Microwave Interactions of Snow-Covered Arctic First-Year Sea Ice (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/32826https://hdl.handle.net/1880/119998In this thesis, the thermophysical, dielectric and Ku-, X- and C-band polarimetric microwave properties of relatively smooth snow covered first-year sea ice (FYI), from late-winter to pre-early melt onset thermodynamic regime are investigated. Fully-polarimetric microwave backscatter data acquired from a unique, surface-based multi-frequency (Ku-, X- and C-band) scatterometer system is used near-coincident with in situ snow thermophysical measurements, to investigate thermodynamic and electrical state of snow covered FYI. Using a first-order microwave backscatter model, a multi-frequency framework is theoretically established to determine the dominant snow thermophysical properties sensitive to the modeled microwave backscatter, at Ku-, X- and C-band frequencies. Multi-frequency microwave observations acquired from the scatterometer system are then used to inter-compare with modeled backscatter, to investigate the potential of the surface-based system to determine the thermodynamic and electrical state of snow covered FYI, at diurnal and temporal scales, from late-winter to pre-early melt onset. A unique frequency-dependent polarimetric parameter is developed to characterize frequency-dependent changes in microwave backscatter, as a function of snow thickness, polarization and incidence angle. Theoretical and observational findings indicate significant influence of snow salinity affecting microwave propagation through snow covers on FYI, for all three frequencies. These findings are utilized semi-empirically to develop a thickness-dependent snow salinity correction factor to improve FYI freeboard and thickness measurement retrievals from space-borne radar altimeters, operating at Ku-band.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Remote SensingSea IceArcticSnowRadarClimateGeographyOceanographyRemote Sensingdoctoral thesis10.11575/PRISM/32826