Experimental Product Maps
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Current Conditions
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Forecast
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Image Archive
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Data Archive
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Live Fuel Moisture
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US48
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The Experimental Live Fuel Moisture images (Burgan and Hartford 1997) portray an estimate of
live shrub moisture contents and will give best estimates in plant
communities that are dominated by shrubs. The base moisture content
range for each pixel has been determined using maximum and minimum
NDVI images for the historical period dating back through 1989. For
example, areas with historically low minimum and maximum NDVI
generally correspond to arid communities and yield minimum
calculated moisture contents as low as 50% on a dry weight basis.
Maximum moisture content in the most arid sites will be at least
100% but may range higher. Very moist sites may range from a
minimum of 90% to a maximum of 250%.
The Relative Greenness image data is used to
determine the weekly moisture estimate within each pixel's
potential moisture range as follows: pixel mc = ((RG/100) * pixel
mc range) + pixel mc minimum. Where mc is moisture content on a dry
weight basis and RG is the Relative Greenness pixel value for the
week. Use caution with the moisture image if there are clouds or
smoke in the area of interest because they diminish the measured
plant reflectance and artificially lower the calculated moisture
content. The moisture image will be most useful in those shrub
communities where users have measured live fuels (ground truthed)
and developed correlations between measured and image moisture
values.