Soil Moisture Retrieval Using the Danish L- & C-Band Polarimetric SAR - Geoscience and Remote Sensing Symposium, 1996. IGARSS '96. 'Remote Sensing for a Sustainable Futur

Danish polarimetric SAR data have been applied t o estimate soil moisture (SM). The preliminary results evaluated with the Land C-band SAR dat,a acquired at the Danish test site Foulum during a number of missions in 1994 and 1995 are presented. In situ data have been collected during the SAR missions and the variations of SM at field scale are discussed. The Integral Equation El]. In addition, Dubois and Oh have developed two different empirical models [a, 31. The empirical models are much simplified compared to the IEM. In this paper, the Danish Land C-band polarimetric SAR data acquisitions and the zn sztu data collections are described. SM variations at field scale are illustrated. The Dubois model, the Oh model and the IEM have been applied for SM retrieval. Method (IEM), the Dubois empirical model and the Oh polarized-ratio model have been used as algorithms to inverse SM from polarimetric SAR data under near bare field conditions. Comparisons between the inversions and the in situ measured data showed that the Dubois empirical model gave the best results for inversion of SM. The standard deviations between the inversed and the measured data at C-band are smn = 6.1% for SM and s, = 0.37cm for soil surface rrns height, respectively. C-band data are better than L-band data for estimation of surface roughness.