|
|
The MERIS sensor and the Globcover Project 
b) The GlobCover project The GlobCover initiative was developed to generate a global land cover map for the years 2005 and 2006. The service was designed in a way that would make it possible to update the map. It is an ESA initiative that was launched in 2005, and is led by an international network of partners including EEA, FAO, GOFC-GOLD, IGBP, JRC, and UNEP. GlobCover uses Envisat’s MERIS fine resolution (300m) source mode data acquired between the end of 2004 and mid 2006 as its main data source. For maximum user benefit, the thematic legend was made compatible with the UN Land Cover Classification System (LCCS). The following GlobCover products are generated on a global scale with a spatial resolution of 300 metres:
The MERIS FR Composite products are temporal composites of surface reflectance generated on a bimonthly and annual basis. They are an output of the GlobCover pre-processing chain applying geometric and radiometric corrections. The bimonthly MERIS FR composite is computed every 2 months and provides, for each spectral band, the average surface reflectance calculated from all valid observations of this 2-month period. The annual MERIS FR composite is computed by averaging the surface reflectance values of the bimonthly product over an entire year.
The bimonthly composites are the products we are going to use when we compare them with the SPOT VEGETATION NDVI product. NDVI is already calculated in this product, following the quality controls stipulated.
Last update: 16 April 2013
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||
