Spatial Analysis 2

As global climate change continues to alter local and state patterns of vegetation growth and weather an ever increasing demand for rapid collection and analysis of data is created.  As climate change is increasing average summertime temperatures and decreasing rainfall throughout the winter more extreme fire conditions are being created that are sweeping through Northern and Southern California.  Fire crews are burdened by more work than they can possibly handle without calling in extra support from all over the state and nation.  Fire crews can be more efficient if they are given as much information about potential fire hazard areas before the fires start. This way they can address these areas using mitigation tactics before fires start.  If fire crews know that an area is prone to extreme fire behavior they can perform vegetation management techniques such as clearing the brush ahead of time, doing controlled burns, or speaking to homeowners about managing their properties responsibly.

A site analyses can be used like the one in this lab to determine areas that are more hazardous than others when exposed to fire. Factors in this lab were slope and vegetation type. Of course other factors exist in determine the extremity of a fire like wind, relative humidity, and elevation, but for the purposes of this lab we are only taking into account these two factors.  The lab focus was on the station fire location which occurred in Los Angeles County in the summer of 2010. The slope factor was created from a digital elevation model obtained from the USGS seamless server application, using the spatial analysis/slope tool in ArcGis. Once a slope layer was created it was then reclassified into different categories of increasing hazard levels, steeper being more hazardous.  A similar task was performed using a raster layer of vegetation types throughout Los Angeles. The vegetation layer was converted into vector format and then reclassified using NFPA vegetation standards to classify the hazard level of each vegetation type.  Once both slope and vegetation layers were reclassified into hazard level layers they were combined into one hazard layer using the raster calculator. The layer you see covering the station fire shows the overall hazard levels given slope and vegetation type.

The map that was created during this lab can be extremely useful in explaining why the Station fire was as intense and devastating as it was. Almost the entire area was very steep and covered by chaparral type vegetation that burns very well. Other factors that are not displayed in the map are the wind and the temperatures during the fire.  These factors also play a very large role in a fires’ ferocity, but are more difficult to create a map layer from because of their rapidly changing nature.  Aside from these minor deficiencies, site analyses can still be an extremely powerful tool when implemented into certain fields such as fire behavior.  With the addition of some remote sensing technology and a fast computer processor this operation could be done in a matter of hours for the entire state of California making it extremely valuable for wildland fire department throughout the country.