Emissivity of snow-covered terrains for spaceborne applications

For space-borne monitoring of snow properties, both surface and atmosphere properties have to be retrieved. Passive microwave measurements of snow surfaces show a large variation of the observed brightness temperature, which depends amongst others on snow temperature and snow water equivalent. Measured microwave radiometer data from the Weissfluhjoch (Switzerland) are used to evaluate the effects of the snow characteristics on the polarisation and frequency dependent emissivity. ESA´s Multi-frequency Imaging Microwave Radiometer (MIMR) is designed to open new fields of applications, especially for land applications. Recommendations for algorithm development are given using emission simulation and SSM/I observed brightness temperatures from the Hardangervidda test site in South Norway