Snow satellite algorithm development and verification based on the ground snow observation using a ground microwave radiometer

摘要

This paper develops a new snow algorithm for the Advanced Microwave Scanning Radiometer (AMSR) and the AMSR for Earth Observation System (AMSR-E) and validates the algorithm by using the snow depth data observed at Sapporo, JAPAN. A new radiative transfer model for layered snow is developed by combining the 4-Stream Fast Model and the Dense Media Radiative Model and is introduced into the new algorithm. Effects of the snow particle grain size on brightness temperature observation in the microwave region are considered in the algorithm by using the multi-frequency channels of AMSR and AMSR-E. The algorithm was validated for the period from October 2004 to March 2005, using ground based brightness temperature observation, observed during field experiment in Sapporo. The estimated snow depth is not in good agreement with the in-situ data when snow pack is moist. However, the estimated snow depth is in good agreement with the in-situ data for dry snow condition.