The GlobAlbedo project was funded by the Data User Element of ESA's Earth Observation Envelope Programme.

Land surface albedo determines the amount of solar radiation absorbed by the Earth's surface, and due to the heterogeneity of land cover, is one of the major uncertainties in modelling the surface energy budget. Satellite observations are the only practical means to measure albedo globally, and to help reduce these uncertainties.

A land surface broadband albedo map of the entire Earth’s land surface, including snow, was required for use in Global Climate Model initialisation and verification as well as in hydrological modelling of Soil-Vegetation Transfer Schemes (SVATS).

To achieve the aim of deriving independent estimates using European only assets, GlobAlbedo set out to create a 14 year time series by employing SPOT4-VEGETATION, SPOT5-VEGETATION2 as well as ENVISAT-MERIS. Legacy algorithms for deriving spectral Bi-directional Reflectance Factors (BRFs) using an optimal estimation approach as well as the use of a prior estimation dataset called a “prior” derived using a novel system for gap-filling using ten year mean estimates derived from the US MODIS sensor. Each and every output pixel albedo (DHR, BHR) value has an estimated uncertainty associated with it and the corresponding BRDF has a full variance-covariance matrix for each and every pixel.

The land surface albedos have been generated at 1km (in MODIS SIN tiles), 0.05 º and 0.5º grid resolution in Plate Carree every 8-days.

Further information as well as full or subsetted data downloads can be found at the website linked below.