Level-2 VG1 and V10
The Level-2 VG1 and V10 SYN products (SY_2_VG1 and SY_2_V10 respectively) are produced by the SYNERGY Level-2 processor and contain 1 km VEGETATION-like product ,1 and 10 days synthesis surface reflectances and NDVI. The product grid and the four spectral bands are similar to the SYN Level-2 VGP product.
These products are provided by small software dedicated only to the combination and the production of the VGT-S product. This software takes as input the VGK products.
These products are a maximum Normalised Difference Vegetation Index (NDVI) value composite of ground reflectance measurements of all segments received during 1 or 10 days for the entire surface of the Earth. It can be ordered in a map projection specified by the user, covering the whole world or a region of interest defined by the user.
Note that in the frame of coming evolutions, the "max NDVI" composite method could be replaced by a different one.
SYN VG1 corresponds to the daily synthesis, i.e. the single "best" value for Top of Canopy (TOC, i.e. after an atmospheric correction) reflectance at the four selected channels, based on those giving the maximum value of a vegetation index.
SYN V10 product provides, for each spectral band (B0, B2, B3, MIR) a decade synthesis of surface reflectance, defined at TOC. This synthesis is formed using the maximum value composite over the 10 day period.
In addition, the NDVI is provided. It is derived from the B3 and B2 channels and can be defined as an indicator of vegetation amount.
The parameters included in annotation files are similar to the ones included in the SYN Level-2 VGPT package, with the exception of synthesis time. In this product, annotation data are provided for each pixel and not on a sub-sampled grid.