Evaluation of NDVI for monitoring live moisture in three vegetation types of the Western U.S.

been estimated through empirically derived algorithms or The Normalized Dimence Vegetation Index (~~vr) is evalu- Was measured using intensive field methodology. ideally, inated for monitoring seasonal a Burgan et al., 1997). The Advanced Very High Resoluthan the conifer canopy was examined. Seasonal changes in tion sensor On the TIROS-N series vegetation moisture for all sites were statistically significant polar-orbiting weather satellites provides daily observations (p<0.05). Time-series profiles of the NDVI were functionally of the Earth's mrface at a nominal spatial resolution (at narelated to changes in vegetation moisture only for the grass dir) square lcrn. it was and forest understory vegetation. N~ significant relationships with natural resource observation objectives, several indices were observed for either the shrub or coniferous forest can- derived the AVHRR Vectral data provide meaningfu1 opy vegetation. This field experiment will improve our inter- measures of vegetation condition (Loveland and ~hlen, pretation of seasonal NDVI data with respect to fire potential. lgg3). The lIifference Index (NDvl)*