Inversion model validation of ground emissivity. Contribution to the development of SMOS algorithm

TL;DR

This paper validates an inversion model for ground emissivity to improve the SMOS satellite's soil moisture and salinity measurements, focusing on the impact of litter layers on emissivity correction.

Contribution

It introduces a simple analytical model of litter effects on emissivity, integrated into the SMOS algorithm for better ground moisture and salinity mapping.

Findings

Validated the analytical model with radiometer measurements

Demonstrated improved correction of vegetation effects

Highlighted the significance of litter layers in emissivity modeling

Abstract

SMOS (Soil Moisture and Ocean Salinity), is the second mission of 'Earth Explorer' to be developed within the program 'Living Planet' of the European Space Agency (ESA). This satellite, containing the very first 1.4GHz interferometric radiometer 2D, will carry out the first cartography on a planetary scale of the moisture of the grounds and the salinity of the oceans. The forests are relatively opaque, and the knowledge of moisture remains problematic. The effect of the vegetation can be corrected thanks a simple radiative model. Nevertheless simulations show that the effect of the litter on the emissivity of a system litter + ground is not negligible. Our objective is to highlight the effects of this layer on the total multi layer system. This will make it possible to lead to a simple analytical formulation of a model of litter which can be integrated into the calculation algorithm of SMOS. Radiometer measurements, coupled to dielectric characterizations of samples in laboratory can enable us to characterize the geological structure. The goal of this article is to present the step which we chose to validate this analytical model.