Infrared Aerial Photography - Sacramento, CA

http://www.aerialarchives.com/infrared.htm

Infrared sensors and film only detect emitted radiation in the infrared band.  This band can be extremely useful in determining the health of vegetation, marhshes, bays, and oceans.  This is done by examining the varying amounts of radiation from smaller, more specific, bandwiths that are emitted by the environment.

In the above picture, the Sacramento Deep Water Channel is captured aerially (and in infrared).  Through this we can determine the health of the vegetation relatively easy.  The areas that are red are emitting the greatest amount of infrared energy and can therefore be deemed "healthy" vegetation.  If we look at the surrounding areas to the healthy vegetation, there are areas of dark blue and green which correspond to low amounts of emitted infrared radiation.  This means that this area has small (if any) healthy amounts of vegetation.  In this image, the health of the surrounding water isn't as easily determined as the land.