Dependence of thermal infrared emissive behaviors of snow cover on the surface snow type

DOI IR HANDLE 2 Citations Open Access
  • HORI Masahiro
    Earth Observation Research Center, Japan Aerospace Exploration Agency Earth Observation Research Center, Japan Aerospace Exploration Agency
  • AOKI Teruo
    Meteorological Research Institute Meteorological Research Institute
  • TANIKAWA Tomonori
    Earth Observation Research Center, Japan Aerospace Exploration Agency Earth Observation Research Center, Japan Aerospace Exploration Agency
  • KUCHIKI Katsuyuki
    Meteorological Research Institute Meteorological Research Institute
  • NIWANO Masashi
    Meteorological Research Institute Meteorological Research Institute
  • YAMAGUCHI Satoru
    Snow and Ice Research Center, National Research Institute for Earth Science and Disaster Prevention Snow and Ice Research Center, National Research Institute for Earth Science and Disaster Prevention
  • MATOBA Sumito
    Institute of Low Temperature Science, Hokkaido University Institute of Low Temperature Science, Hokkaido University

Bibliographic Information

Other Title
  • Dependence of thermal infrared emissive behaviors of snow cover on the surface snow type（雪面の熱赤外射出特性の雪質依存性）

Search this article

Abstract

The potential of the thermal infrared (TIR) remote sensing for discriminating surface snow types was examined by analyzing TIR radiances acquired from space over the Greenland ice sheet.　The brightness temperature difference (BTD) between TIR wavelengths of 11 and 12μm was found to increase in accordance with in situ observed evolutions of surface snow type.　Spatial and temporal distributions of BTD over the entire ice sheet indicated that BTD has a sensitivity of about 1.2 K for variations of the possible snow types.　The observed behaviors of BTD were coincident with those predicted by a radiative transfer calculation using previous in situ measured snow emissivities, although some biases on the order of 0.1-0.3 K remain.　The dependence of BTD on the surface snow type was also consistent with the behaviors of snow reflectance at the shortwave infrared (SWIR) wavelength 1.6μm, which is a measure of snow grain size, except for the case of melting wet snow.　The inconsistency in the wet snow case was considered to be due to the different optical responses of the TIR and SWIR signals to wet snow, which suggested the possibility of using TIR signals to discriminate wet/dry conditions of snow cover in an old stage.　As a result, it is determined that TIR remote sensing has potential not only as an approach supplementary to the SWIR method for assessing surface snow types in daytime but also as the only method for simultaneous retrieval of snow type and surface temperature in nighttime.

Journal

Citations (2)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top