STAR - Global Vegetation Health Products : Browse Archived Image of selected administrative region
Browse VIIRS Images by province : Please select an Image Type, Region, Year and Week.
Click image to see map of the selected country (or international region).
World , Vegetation Health Index (VHI): Current Week and One Year Ago | |
VHI of current year![]() |
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VHI of previous year |
Vegetation Health index (VHI)
Global, 4 km, 7-day composite, validated. VHI=α *VCI + (1- α )*TCI, where α is a coefficient determining contribution of the two indices. VHI is a proxy characterizing vegetation health or a combine estimation of moisture and thermal conditions.VH (VHI, VCI, TCI) is used often to estimate crop condition and anticipated yield. If the indices are below 40 indicating different level of vegetation stress, losses of crop and pasture production might be expected; if the indices above 60 (favorable condition) plentiful production might be expected. VH (VHI, VCI, TCI) is very useful for an advanced prediction of crop losses.
Area without vegetation
For the area without vegetation (desert, high mountains, etc.), the displayed indices characterize surface conditions.GIS information
GIS information of country/international regions and provinces were used for reference only. They were used "as it is" (without checking thier accurary), and there is no garantee they were updated. The sources of GIS related data were obtained from the following web sites:
- Boundary of political regions:
http://www.gadm.org/data/shp/*_adm.zip (GIS shape files) - names of cities:
http://www.naturalearthdata.com/downloads/10m-cultural-vectors/10m-populated-places/ - IGBP land type :
http://edc2.usgs.gov/glcc/globdoc2_0.php (gigbp2_0ll.img.gz, resolution: 1km, lat/lon grid, 43200 x 21600) - Global Land One-kilometer Base Elevation (GLOBE) :
http://www.ngdc.noaa.gov/mgg/topo/gltiles.html (provided as 16 tiles)