Jean-Louis Roujean

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A surface bidirectional reflectance model has been developed for the correction of surface bidirectional effects in time series of satellite observations, where both sun and viewing angles are varying. The model follows a semiempirical approach and is designed to be applicable to heterogeneous surfaces. It contains only three adjustable parameters(More)
Land surface albedo determines the repartition of downwelling solar radiation into components that are either reflected back to the atmosphere or absorbed by the surface. As more sophisticated soil–vegetation–atmosphere transfer schemes are being implemented in numerical meteorological models, it will become increasingly important to accurately characterize(More)
[1] Vegetation attributes impact the Earth’s carbon, water, and energy budgets by controlling the exchanges between the lower atmosphere and the continental biosphere. One of the most important factors is the distribution of the absorbed fraction of solar radiation within vegetation as it constrains the photosynthesis rate. The Interactions(More)
The overall objective of the present study is to introduce the new ECOCLIMAP-II database for Europe, which is an upgrade for this region of the former initiative, ECOCLIMAP-I, already implemented at global scale. The ECOCLIMAP programme is a dual database at 1 km resolution that includes an ecosystem classification and a coherent set of land surface(More)
This paper aims at demonstrating the possibility of merging the data from various medium-resolution space-borne sensors to produce consistent time series of surface BRDF and albedo products. The spectral, directional, temporal and spatial aspects of the multi-sensor fusion are presented. Emphasis is then given on the spectral normalization for the fusion of(More)
In this paper, we present an operational procedure for the inversion of kernel-driven bi-directional reflectance distribution function (BRDF) model and further albedo retrieval to be applicable to the SEVIRI/MSG reflectance measurements. Our approach aims at bringing solutions to an ill posed problem that is when the ratio of extreme eigenvalues of the(More)
The objective of the Cyclopes project is to provide coherent estimates of bio-physical variables such as land surface albedo and leaf area index at regional and global scales and to demonstrate their application in the fields of land cover change detection and carbon cycle modeling. An essential element of the project strategy is to provide(More)