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As urbanization spreads into surrounding natural areas, the chance for confrontation escalates. Such confrontation may be a wildfire. A need then arises for a tool to manage the fire as well as its aftermath. One such tool may be remote sensing.
Remote sensing data have two important characteristics not found in aerial photography. The first is the ability to provide a repeatable, synoptic view of large areas at low cost. Secondly, remote sensing has the ability to "see" in wavelengths that the human eye can not. This extended vision is more sensitive to certain materials and properties, and may aid in their identification. Satellite and airborne imagery are used in both ways by Scottsdale.
In July 1995, a lightning-caused fire erupted in northern Scottsdale. Aided by high winds, the fire quickly spread and threatened subdivisions. A serendipitous overflight of a NASA research aircraft containing infrared sensors was diverted from its course and asked to "image" the fire. These sensors were able to "see through" the billowing smoke and show exactly where the fire was still raging and the direction it was traveling. This information was relayed to fire command center and resources were re-directed to the hot spots. By better use of resources, the fire was extinguished a day early, which saved over $250,000.
Remote sensing may be a useful tool in managing a wildfire's aftermath. Landsat TM satellite data of northeastern Maricopa County shows a variety of fire-scar ages. The most recent fires appear as a fresh scar on the landscape. As grasses come back, along with higher succession shrubs, the increased biomass becomes apparent even from 438 miles in space. By selecting appropriate bands and image processing techniques, images can be generated that show where plant material increased. Change detection images may prove useful in monitoring post-fire.