Using Optical Satellite based Data to Improve Soil Moisture Retrieval from SMOS Mission

SMOS mission will provide micro-wave soil emission data at L-band (1.4 GHz) at global scale with a half-degree spatial resolution. Inversion of model emission permits to retrieve surface soil moisture from SMOS data. These retrievals suffer from a lack of accuracy mainly because of the heterogeneity of land coverage encountered inside a given pixel. The addition of land surface parameters such as vegetation fractions coverage and surface temperature permits to overcome this problem. A feasibility study is presently undertaken with synthetic SMOS data and simulated optical satellite information. The results present significant improvements of soil moisture retrieval accuracy. A future operational scheme including these features will be of relevance for a global surface soil moisture mapping.