The Study Of The Polarized Factors Of Snow Surfaces And Its Relationship With Snow Properties

The snow cover is one of the most active particulate surfaces on the Earth, andthe changes of snow property relates to the environment condition. Snow albedo isalso the indicators of climate research and snow cover. Therefore, monitoring thesnow is important for the application to global climate change and water resourcesmanagement and prediction. Remote sensing technology is a valid method forobtaining information to invert the characteristic parameters of snow surface fromalpine areas, polar region and hard access area. The applications of remote sensingtechnoloty in snow monitoring mainly take advantange of the snow surface reflectionand radiation using sensers, and analysising the snow parameters from theseinformation. Remote sensing technology can be anti-the performances snowcharacteristics according to the different time series and spatial scales, climate modelsand hydrological models for different scales, which also provides the necessary andaccurate input parameters.For passive remeote sensing, in which snow will be in the process of reflectionand radiation due to the change of itself, the sensor detects these information todistinguish the different characteristics of the snow table. Among the snow surfaceelectromagnetic wave interactions, polarization is ofter ignored The light reflected bythe snow surface contains rich polarized signals, especially in the polar and alpineregions. With Sun incident angles increasing, this makes the detector obtain morepolarized information and with incident zenith angle and detection zenith angle, theemergence of the use of the existing remote sensing model inversion of snowparameters causes large errors. Therefore, whether it is for a more complete anddetailed understanding of the snow surface with electromagnetic radiation process orexplore possible use of polarization information reflects the snow parameters in largeincident zenith angle and viewing zenith angle, the study of the polarization propertiesof snow should is an integral part of snow in remote sensing.In this study, we mainly focused on two aspects, a theoretical basis for therelationship between the processes of radiation transfer theory, the Stokes parameterswith the snow surface reflection and emission polarization characteristics, systematicand comprehensive analysis of the first study for the snow surface in the direction ofthe polarization information characteristics and polarization spectral characteristics.The reflective properties of snow in visible and near-infrared bands and emissionpolarization properties of the thermal infrared band; followed through the snow in thevisible and near infrared polarized reflectance information reflects the characteristic parameters, trying to establish between the polarization properties of snow and snowparameters relationship. The results show that:The reflected information of snow surface in the range of visible andnear-infrared wavelength range contains polarization information, and there is a cleardirectional characteristics found in the snow surface reflection for all the informationpolarization measurement process. The polarization information of the first reflectedlight to the scattering direction is most intense, especially in the principle plane; thenappears to the scattering direction of negative polarization Polarization properties ofsnow emitted radiation in the thermal infrared band information is also found, butmainly relate to viewing zenith angle, and anisotropic features is more obvious withthe viewing angle increasing. At the same time, the wavelength dependence isappeared for thermal polarization.The degree of polarization as an indicator in the course of the study of therelationship between the polarization information and snow parameters, we find thatthe degree of polarization of snow is sensitive to grain size, especially in the visibleand near-infrared band; we can take advantage of the degree of polarization todistinguish snow grain size The degree of polarization of wet snow is smaller than thedegree of dry old snow. Contaminants in the snow also affect the polarized property ofsnow.In short, the polarization properties of snow can be important for understandingthe interaction between snow surface and electromagnetic waves; the exploration ofthe polarization properties of snow parameters relations to the remote sensingtechnology provide a new understanding of the use of polarization information on thetheory and methods. In this study we combine angle information, polarization with thesnow parameter information, not only analyze the effect of varied angle on thepolarization, the relationship between the polarized reflectance and bidirectionalreflectance, but also consider the influence of snow parameters. Strive to learn moreabout snow polarization properties based on the use of polarization informationreflects the snow parameters characteristics. This is useful for the theoretical andpartical significance for the realization of polarization remote sensing monitoring ofsnow. Also in the snow monitoring the theoretical basis of remote sensing technologyhas opened up new ideas and the direction of the broader areas of remote sensingmethods to obtain information, which can get more information for the inversion ofsnow parameters using remote sensing.