In drylands the annual maximum NDVI is reported to be a better
estimate than average NDVI, also having less of a risk of
cloud contamination.
The maximum annual NDVI over the Sahel was taken from NOAA-AVHRR, and
calculated from reflectance in the near infrared (NIR)
and visible (VIS) regions:
NDVI = (NIR-VIS)/(NIR+VIS)
THe data used here is in 8 km resolution and was pre-processed by
the GIMMS (Global Inventory Monitoring and Modeling System)
group at NASA's Goddard Space Flight Center.
To see maximum NDVI for individual years click on the time-table below the map.
