Global Scale Monitoring of Soil and Vegetation using Active and Passive Sensors

The potential of SSM/I data in monitoring land surface features and global changes in synergy with the ERS Wind-Scatterometer was investigated. The backscattering coefficient, the brightness temperature, and some related quantities, measured during a yearly cycle on a number of selected test sites in different climatic regions of the world, were related to surface features obtained from ground information. The major characteristics of land surfaces were obtained from their emissivity spectra and polarization state, while a further classification of surfaces were carried out by means of multi-frequency, dual-polarized data. Vegetation biomass and snow cover were estimated from appropriate microwave indexes and from spectra of brightness temperature.