On Estimation of snow water equivalence using SIR-C/X-SAR
نویسندگان
چکیده
Snow water equivalence, which is the product of snow density and depth, is the most important parameter in snow hydrology. This paper demonstrates the algorithms for estimating dry snow density, depth, grain size, underground dielectric constant and surface RMS height using multi-frequency and –polarization SAR (SIR-C/X-SAR) measurements. The algorithms were developed based on the numerically simulated backscattering coefficients. We used L-band VV and HH to estimate snow density and the under-ground surface parameters: dielectric constant and roughness RMS height. The under-ground surface can be either soil or rock. Then, C-band VV, HH and X-band VV are used to estimate snow depth and grain size.
منابع مشابه
Estimation of snow water equivalence using SIR-C/X-SAR. II. Inferring snow depth and particle size
The relationship between snow water equivalence (SWE) and SAR backscattering coefficients at Cand X-band (5.5 and 9.6 GHz) can be either positive or negative. Therefore, discovery of the relationship with an empirical approach is unrealistic. Instead, we estimate snow depth and particle size using SIR-C/X-SAR imagery from a physically-based first order backscattering model through analyses of t...
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