Extent of available data.
This data layer is a Normalized Difference Vegetation Index (NDVI). It was developed by the Natural Resources Research Institute. An NDVI is an indicator of live vegetation. It was calculated at the 10 meter grid scale using imagery from the Landsat satellite and Google Earth Engine. The formula is: NDVI = (Near InfraRed - Red)/(Near InfraRed + Red). Since the NDVI relies on satellite imagery, it can be calculated over large extents. This makes it useful as a uniform metric of vegetation over large areas. The NDVI is also considered a useful input for some predictive landscape models.