Assessing Fire Extent

The spectral and spatial resolution of the Landsat 7 ETM+ sensor makes it a useful tool to chart environmental change. As a consequence of the vertical integration of the scenes to the Texas Reference Frame, other GIS data layers useful for analysis can be overlain with minimal processing. The images can also be used as a mapping reference. Information digitized from the color composite, such as the fire extent, can be transferred to higher resolution digital orthophotography for refinement.

In these color infrared composites, green forest vegetation appears deep red. Dry vegetation and sparsely vegetated areas are gray and tan. It is possible to discern highways and dirt roads. The May 4 scene is cloud-free while some patches of low-lying bright white cumulus cast deep shadows near the center and on the lower right.

Landsat 7 passed over the Glass Mountains on the same day that lightning sparked the fire, capturing an image of the landscape and environment before fire transformed it into what is seen below. The charred aftermath of the blaze is evident in the subsequent image collected by the sensor.