Polarimetric C-band Microwave Scattering Properties of Snow Covered First-Year Sea Ice

• Main Author: Gill, Jagvijay P. S.
• Other Authors: Yackel, John
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Graduate Studies 2014
• Subjects: Geography; Geophysics; Remote Sensing; Synthetic Aperture Radar; Microwave; Polarimetry; Snow; Sea Ice; Classification; Sea ice
• Online Access: http://hdl.handle.net/11023/2096; https://doi.org/10.11575/PRISM/27376

In this thesis, the physical, dielectric, and C-band polarimetric microwave properties of snow covered first-year sea ice (FYI) at different temperature conditions, largely encompassing late winter to melt onset period are investigated. First, a set of polarimetric parameters derived using different decomposition and synthesis techniques are analyzed at cold temperature conditions by relating them to pre-identified sea ice types. These parameters are further analyzed for their sea ice classification potential. This analytical scheme is extended to warmer temperature conditions and their stability for ice type signature response and classification potential is assessed. Second, the polarimetric SAR response from snow covered FYI at cold temperature conditions is analyzed to investigate the sensitivity of polarimetric backscatter to snow thickness. The backscatter sensitivities are examined as a function of change in surface air temperature through the changes manifested in snow geophysical properties. Lastly, in-situ measured geophysical and dielectric properties of thick and thin snow cover over smooth FYI and the corresponding C-band scatterometer measurements are analyzed at diurnal time scales during the transition from early melt to melt onset. A simple, multi-layer surface and volume scattering model of snow covered FYI is adopted. Using in-situ snow properties for model parameterization, corresponding C-band backscatter response is evaluated and scattering mechanisms are theorized. The findings indicate additional information is provided from fully polarimetric C-band backscatter data for sea ice classification and snow thickness retrieval purposes. Results also suggest that these parameters are best estimated at low radar incidence angles and during the late winter to early melt timeframe.