Assessment Products

Vegetation and Fuel Information

WFAS Live Fuel Moisture -- Greenness Maps

Four vegetation greenness maps are derived weekly from Normalized Difference Vegetation Index (NDVI) data observed by satellites and provided by the EROS Data Center, U.S. Geological Survey. These maps have a 1 kilometer (.6 mile) spatial resolution. Maps with historical references (RG and DA) are based on the years 1989 through 1995. The derived maps are:

• Visual Greenness Maps - portray vegetation greenness compared to a very green reference such as an alfalfa field or a golf course. The resulting image is similar to what you would expect to see from the air. Normally dry areas will never show as green as normally wetter areas.
• Relative Greenness Maps - portray how green the vegetation is compared to how green it has been historically (since 1989). Because each pixel is normalized to its own historical range, all areas (dry to wet) can appear fully green at some time during the growing season.
• Departure from Average Greenness Maps - portray how green each pixel is compared to its average greenness for the current week of the year.
• Live Moisture Maps - portray experimental live vegetation moisture with values ranging from 50 to 250 percent of dry weight.
  

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  ** The above information is from the WFAS web site: http://www.fs.fed.us/land/wfas/welcome.html

Greenness Maps		Counterminous US	Alaska
Visual Greenness	1 panel, 250K bytes	US	AK
Relative Greenness	1 panel, 150K bytes	US	AK
Departure From Average Greenness	1 panel, 150K bytes	US	AK
Experimental Live Moisture	1 panel, 150K bytes	US	AK
Visual/Relative/Departure/Moisture	4 panel, 150 K bytes	US