Multi-Spectral Remote Sensing of Brush Fire Scars in Arid Urban Regions: Analysis of Future Fire and Flooding Hazards

NASA Research Announcement NRA-98-OES-13

Principal Investigator: Michael Ramsey
Co-Investigator: Ramon Arrowsmith
Department: Geology and Planetary Science
Institution name: University of Pittsburgh
Budget: $162,585 for 3 years

Program Areas:

II. Topography & Surface Change
  1. GPS and INSAR Applications
  2. Global Sea Level Change
  3. Coastal Hazards
  4. Flood Disaster Management Applications
  5. Landslides
  6. SRTM/Topography and Surface Change
    _______ _______ _______ ___X___ _______ _______

IV. Thermal and Geothermal Hazards
  1. Wildfires
  2. Volcanic Hazards
    _______ ___X___


We propose a multi-frequency, multi-temporal analysis of existing brush fire scars for Phoenix, AZ and other semi-arid urban environments. This analysis will be used to develop a model of flash flooding potential and future fire hazards for these regions. Because of the removal of vegetation due to these fires, subsequent channel and surface flooding increases during intense periods of summer monsoonal thunderstorms. Further, many of these regions are undergoing rapid urbanization and the threat to human lives and property will increase. Because the southwestern United States has the highest urban growth rates in the nation, cities must address a broad range of issues, including water resources, urban growth, and natural hazards such as brush fires and flash flooding. As populations in these regions continue to grow and the urban fringe expands into the vegetated desert, more and more people are at risk from human- and naturally- induced fires. Once burned, these regions then can facilitate and concentrate rapid flood run-off and erosion. Factors that influence these fire scars are the proximity of human activity, short and long term climate variations and vegetation type and abundance.

We intend to utilize currently available multi-spectral, multi-temporal data archive of images to analyze existing fire scars surrounding the Phoenix area. These scars range in age from 3 to 30 years are easily visible on near-infrared, thermal-infrared surface temperature, and SIR-C radar images. The first stage of this study will be to investigate the linkage between the fire scar age, vegetation type and recovery, soil type and local topography. Next we will use this information to model surface response to heavy rainfall and asses the local hazard potential. By utilizing these data together with new field studies, we will concentrate on developing a flood/fire hazard map of the Phoenix region and identify the most efficient means of remote detection. The final stage of the study will be to use these initial results to examine other arid cities in the southwestern United States which have far less remote sensing coverage. This study will serve as a critical facet of the upcoming ASTER global urban monitoring program for which the PI is responsible. This project-approved effort is designed to gather data over the world's 100 fastest growing and environmentally at-risk cities, most of which are located in semi-arid climates.

Accepted: 10 September 1999