This series of maps shows how the effects of slope and vegetation fuel on fire hazard differ across space. Using the Station Fire of 2009 as the study area, various data sets were obtained from the USGS and California Department of Forestry and Fire Protection. These included a digital elevation model (DEM), fuel risk data, vegetation data, and fire perimeter data. The data were then processed for hazard analysis, a technique used by fire prevention, urban planning, and forestry professionals.
The analysis took place in several steps. After creating a hillshade layer from the DEM, slope percent was calculated and reclassified to the NFPA 1144 standard. Greater slope means greater fire hazard. In a similar fashion, the fuel hazard data also was reclassified to the NFPA 1144 standard. Certain vegetation types burn more easily than others. Finally, both the slope and fuel hazard scores were combined into one map, showing a more complete assessment of fire risk.
My greatest challenge was data compatibility, especially with the fuel layer. Instead of reclassifying the fuel data, I had to edit individual values in the attribute table. Analysis proved to be even more difficult. Although I was able to convert both the slope and fuel hazard layers to raster format, something in the fuel layer prevented me from running the raster calculator. The Combined Slope and Fuel Hazard map (adapted from the CA Department of Forestry and Fire Protection) is similar to what a successful calculation would have produced. Issues with data compatibility may have been related to projection.
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