Remote sensing of snowpack by microwave radiometer mounted on satellite

Abstract

This paper uses measured data to analyze the relationship between the depth of the snowpack and the brightness temperature in the snowpack observation by microwave scanning radiometers (MSRs) on Marine Observation Satellite-1 (MOS-1) that is one of the satellite-borne microwave radiometers. In the analysis, a model is established in which the brightness temperature observed by the MSR captures mainly the effect of attenuation by scattering and absorption when the microwave radiated from the underlying ground passes through the snowpack. The measured data are statistically processed by taking into account the fluctuations of the data caused by the effect of various factors other than snowpack on brightness temperature. The MSR data from observations of the Hokkaido region from January to March in 1988 and the snowpack depth data observed on the ground are compared. It is found that the relationship between snowpack depth and the brightness temperature can be approximated by a straight line with a negative slope. The slope of the approximated straight line varies seasonally and this change reflects variations of the snowpack condition. Further, it is shown that there is a strong correlation between the average brightness temperature of the inland part of Hokkaido and that of the ocean surrounding Hokkaido. A possibility is suggested that the effect of atmospheric radiation can be estimated from the average brightness temperature of the nearby ocean. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80(3): 58–66, 1997