[Analysis of the polarization properties of snow in a different melting state].

Nowdays, under the circumstance of global warming, the traditional study of solid-state snow can not meet the current needs. The present paper involves qualitative analysis of the polarization reflectance spectrum of snow in a different melting state. Special attention is paid to the investigation of the relationship among polarization angles, azimuth angles, the light incidence zenith angles, the detection zenith angles and the different types of snowmelt. It turns out that all these factors have certain influences on the polarization reflectance spectrum of different types of snowmelt. At the waveband of the visible light, the polarization reflectance of snowmelt is the largest at 90 degrees, and the smallest at 0 degrees. The wider the detection angles and the incidence angles, the larger the polarization reflectance. Anomalies (unusual phenomena), different from other spectra, occur when the polarization reflectance spectrum of snowmelt is observed at different azimuth angles. The characteristics of polarization spectra at some certain wavebands play an important role in determining the water content of snowmelt, and meanwhile with the increase of which, the polarization reflectance will go down obviously. These rules have laid a solid foundation for the quantitative analysis of snowmelt properties by using polarization spectrum in the future and are also of great importance in fresh water management as well as monitoring natural disasters such as the spring flood.

[Studies of the thermal radiation characteristics of urban typical surface features].

The use of thermal infrared technology to monitor the land surface temperature has received mature development, and the acceleration of urbanization makes the urban heat effect emerge, thus, studies of the thermal radiation characteristics of urban typical surface features make great significance for the analysis of the causes and distribution of the thermal phenomenon. Based on the study of ground measured data of Baoding city, we have found that, the feature types, the observation time and wall orientations are principal factors that exert an influence on the thermal radiation brightness temperature of urban typical surface features. The results show that different types of surface features will significantly affect the brightness temperature, but "different things with the same spectrum" still exists; the observation time has direct impact on the intensity of thermal radiation and to a large extent on the brightness temperature difference of each channel; the brightness temperature of different wall orientations are also different, and the difference changes with the change in observation time. Studies of thermal radiation characteristics of urban typical surface features have theoretical and practical significance, providing basis for thermal infrared remote sensing to monitor the urban heat effect.

[Study on the reflected and hyperspectral mixed-pixel character of aquatic plants and water].

A study on the reflected and hyperspectral mixed-pixel of aquatic plants and water was given by using a orthogonal experimental design with three factors and two levels. The results of F test suggest that for the single factors, the band and the area ratio of mixed-pixel on the reflected and hyperspectral mixed-pixel of the reflection effects are particularly significant, however, the detector angle had no significant effect under these experimental conditions; For the interaction, the band and the area ratio of mixed-pixel, the detector and the area ratio of mixed-pixel, the effects of these two interactions on the reflected and hyperspectral mixed-pixel are also particularly significant, This study did quantitative analysis of the factors affecting the reflected and hyperspectral mixed-pixel character and their interaction, and provided a new method for the indepth study of mixed-pixel.