Normalized Difference Vegetation Index for Fanno Creek, Oregon

Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the Normalized Difference Vegetation Index (NDVI), or "greenness" of the Fanno Creek floodplain study area. Aerial photography was used to isolate areas of vegetation based on comparing different bandwidths within the imagery. In this case, the NDVI is calculated as the quotient of the near infrared band minus the red band divided by the near infared plus the red band. NDVI = (NIR - R)/(NIR + R).