caa a22 4500 477124445 CHVBK 20180405111645.0 cr unu---uuuuu 170330e19970501xx s 000 0 eng 10.1007/BF02678093 doi (NATIONALLICENCE)springer-10.1007/BF02678093 Estimation of surface snow properties using combined millimeter-wave backscatter and near-infrared reflectance measurements [Elektronische Daten] [Ram Narayanan, Sandy Jackson] Knowledge of surficial snow properties such as grain size, surface roughness, and free-water content provides clues to the metamorphic state of snow on the ground, which in turn yields information on weathering processes and climatic activity. Remote sensing techniques using combined concurrent measurements of near-infrared passive reflectance and millimeter-wave radar backscatter show promise in estimating the above snow parameters. Near-infrared reflectance is strongly dependent on snow grain size and free-water content, while millimeter-wave backscatter is primarily dependent on free-water content and, to some extent, on the surface roughness. A neural-network based inversion algorithm has been developed that optimally combines near-infrared and millimeter-wave measurements for accurate estimation of the relevant snow properties. The algorithm uses reflectances at wavelengths of 1160 nm, 1260 nm and 1360 nm, as well as co-polarized and cross-polarized backscatter at a frequency of 95 GHz. The inversion algorithm has been tested using simulated data, and is seen to perform well under noise-free conditions. Under noise-added conditions, a signal-to-noise ratio of 32 dB or greater ensures acceptable errors in snow parameter estimation. Plenum Publishing Corporation, 1997 inversion nationallicence multisensor nationallicence neural network nationallicence remote sensing nationallicence snow properties nationallicence Narayanan Ram Department of Electrical Engineering, Center for Electron-Optics University of Nebraska, 68588-0511, Lincoln, Nebraska, U.S.A. aut Jackson Sandy Department of Electrical Engineering, Center for Electron-Optics University of Nebraska, 68588-0511, Lincoln, Nebraska, U.S.A. aut International Journal of Infrared and Millimeter Waves Kluwer Academic Publishers-Plenum Publishers 18/5(1997-05-01), 959-990 0195-9271 18:5<959 1997 18 10762 https://doi.org/10.1007/BF02678093 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02678093 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Narayanan Ram Department of Electrical Engineering, Center for Electron-Optics University of Nebraska, 68588-0511, Lincoln, Nebraska, U.S.A aut NATIONALLICENCE 700 1- Jackson Sandy Department of Electrical Engineering, Center for Electron-Optics University of Nebraska, 68588-0511, Lincoln, Nebraska, U.S.A aut NATIONALLICENCE 773 0- International Journal of Infrared and Millimeter Waves Kluwer Academic Publishers-Plenum Publishers 18/5(1997-05-01), 959-990 0195-9271 18:5<959 1997 18 10762 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer