Retrieval of leaf area index by inverting hyper-spectral, multi-angular CHRIS/Proba data from sparc 2003

The SPARC campaign has been organized in coincidence of CHRIS/Proba multi-angular and hyperspectral acquisition over the agricultural test site of Barrax in Spain. Radiometric and biophysical vegetation parameters measurements have been carried out for different crops in both field and laboratory. . The aim of this preliminary study is to assess the capability to estimate Leaf Area Index (LAI) from CHRIS/Proba data by inverting the coupled radiative transfer models PROSPECT+SAILH. Two different approaches have been used to invert canopy reflectance observed in 5 directions and 62 spectral bands: Look Up Tables and Pest ASP Tool. Results show that the use of a priori knowledge is of great importance for the estimation of LAI. In this way we have been able to estimate this parameter with an accuracy of around 15%+20% for Alfalfa, Potatoes, and Sugar Beet samples.