The version 3 CYCLOPES algorithms assess the LAI, Fcover, and FAPAR by inversion of the radiative transfer model SAIL (Verhoef, 1984) using neural networks, which consider as input the solar zenith angle at 10:00 local time and the normalized nadir reflectances in red, NIR and SWIR wavebands. This method, defined by the CSE team of INRA Avignon, is applied to VEGETATION data. CYCLOPES algorithms are presented in Baret et al. (2007).

Fcover over Europe derived from VEGETATION data, August 2003.

LAI, FCover and FAPAR (1999 - 2003) are included in a same product called "Biophysical", which can be downloaded with a readme file. They are provided in tiles of 10°x10° covering the whole globe in plate-carrée projection. The map locating the tiles can be downloaded.
Furthermore, LAI, FAPAR, and FCover are extracted over 323 sites of the BELMANIP database (Baret, et al., 2006) used for validation. These extractions covering about 50km*50km can be downloaded, with a list and description of sites.

CYCLOPES FCover has been validated by comparison with FCover derived from SPOT images at 20m resolution. The latter has been assessed by inversion of SAIL-PROSPECT model using a neural network, and validated by comparison with ground measurements. Then ,the HR maps have been aggregated at 1km resolution to be compared with CYCLOPES FCover (Fillol et al., 2006). Figures below show that the two products display the same spatial patterns, and the same phenological cycles although the CYCLOPES FCover is systematically lower than the SPOT HR FCover.

Spatial comparison (top-left), temporal (over 2 various pixels (top-right) comparison and global comparison (bottom) of CYCLOPES FCOVER and SPOT HR FCover over South West of France in 2002 and 2003 (from Fillol et al., 2006).

Baret, F., O. Hagolle, B. Geiger, P. Bicheron, B. Miras, M. Huc, B. Berthelot, f. Nino, M. Weiss, O. Samain, J.L. Roujean, and M. Leroy, LAI, FAPAR, and FCover CYCLOPES global products derived from Vegetation. Part 1 : principles of the algorithm, Remote Sensing of Environment, 110:305-316, 2007.

Baret, F., J.T. Morisette, R.A. Fernades, J.L.Champeaux, R.B. Myneni, J. Chen, S. Plummer, M. Weiss, C. Bacour, S. Garrigues, and J. Nickeson, Evaluation of the representativeness of Networks of sites for the Global Validation and Intercomparison of Land Biophysical Products : Proposition of the CEOS-BELMANIP, IEEE Transactions on Geoscience and Remote Sensing, vol44, 7, 1794-1803, July 2006.

Fillol, E., F. Baret, M. Weiss, G. Dedieu, V. Demarez, P. Gouaux, D. Ducrot, Cover fraction estimation from high resolution SPOT HRV&HRG and medium resolution SPOT-VEGETATION sensors. Validation and comparison over South-West France, Proceedings of Second Recent Advances in Quantitive Remote Sensing Symposium, pp.659-663, 2006.

Verhoef, W., Light scattering by leaf layers with applications to canopy reflectance modelling : the SAIL model, Remote Sensing of Environment, 16:125-141, 1984.