Estimation Of Errors In Biophysical Parameters Maps Derived From Remote Sensing Data: The SPARC Experiment

Hyperspectral/multiangular data allows the retrieval of important vegetation properties such as leaf area index, fractional vegetation cover, canopy water content and canopy chlorophyll content. Within the overall context of ESA SPARC (SPectra bARrax Campaign) experiment an extensive field campaign in La‐Mancha (Spain) was carried out, simultaneously with the overflight of airborne imaging spectrometers (AHS, HyMAP, ROSIS) and the overpass of CHRIS‐PROBA and MERIS sensors. During the SPARC‐2003 and SPARC‐2004 campaigns a large amount of ground measurements were collected in the Barrax study area (covering LAI, fCover, leaf Chlorophyll a+b, leaf water content and leaf biomass) together with other complementary data and a total of seventeen CHRIS‐PROBA images were acquired. We have focused our analysis on these data with the objective of deriving LAI and chlorophyll maps from CHRIS images by applying different spectral bands combinations, after variability in ground measurements was evaluated by statistical techniques, according to the sampling used in the data collection. A large number of spectral indices have been tested with the available spectral information. From this analysis the error in biophysical parameters has been determined and ways to improve forward modeling have been formulated.