Assignment 8: Mapping the Station Fire in ArcGIS

  Beginning on August 26th, 2009, the Station Fire was estimated to have covered approximately 160,577 acres and killed two firefighters.  It was one of the largest California fires in recent history and destroyed 209 structures.  Much of this fire occurred in the Los Angeles National Forest, and grew in size between August 26th and September 2nd.  The first day of the fire covered a small area and the Forest Service believed they had it under control.  However, by the 2nd and 3rd days, the fire quickly spread and could not be contained causing additional unexpected damage.  The fire threatened radio towers on Mt.Wilson as well as the research facility located there.  

  The fire threatened several communities and evacuation notices were given to many, the extent of the fires in relationship to the county can be seen in the map above..  However after several days of hard work, it was contained and took several weeks after to be considered fully out.  Many factors contributed to the magnitude and damage caused by the Station Fire.  One theory considered the lack of nighttime air water drops as a major factor in the fire spread, while others argued that these additional methods would have had no effect.  The seasonal effect was apparent in weather and wind patterns that aided the fire's growth.  A lack of rain and longer dry season greatly increases the dangers of fire and size of fires that occur.
  By examining rainfall, tree coverage and placement of water bodies, many fires can be analysed carefully.  Water bodies can often block or slow down even fast moving fires.  The presence or absence can have a dramatic effect on the spread and rate of a large fire.  The weather leading up to the fires had been dry and lacking in rainfall.  Many water streams and creeks will dry up if there is not enough waterfall.  One of this category is call intermittent, these water flows usually only appear after rainfall or other means of water movement.  In Los Angeles, the only means is through rainfall, as the area lacks melting snow or ice to create them.  In addition there are perennial streams that last a short time, these can eventually dry if there is not enough rainfall and weather is too hot and dry to permit them to continue flowing.  
  The different kinds of water flows can be seen in the map below.  In the months leading up to the Station Fires, many months of dry weather caused the intermittent streams, seen in the lightest blue to dry up.  This becomes evident because the fire was unaffected by the positions and density of these streams.  The perennial streams, seen in a darker blue were also affected.  It can be seen that the fire spread past these dry riverbeds easily, without hindrance.  In fact, it can often be accelerated as there is more often greater plant density around rivers, but when these streams go dry, it leaves a larger concentration of dry fodder for a dangerous fire.  It is also noteworthy that the minor creeks near the epicenter of the fire seemed to have been unable to contain its spread.  This is because of the intensity and power of the fire, in addition once it has hopped the stream in a single point, it can quickly engulf the entire area on the other side of the creek.

  However, the beneficial effects from water bodies can also be examined on this map.  The creeks to the east, including Aldier Creek and other slowed the fires progress.  It can be seen how to the north and south where these water bodies didn't exist, the fire made much greater progress during its last days of expansion.  However, due to the water bodies and other factors, the fire was slowed in the middle eastern portion.  In fact, the entire eastern portion of the fire can be seen to be bordered by heavier river that could help contain the slower moving outer reaches of the fire.

References
“Station Fire.” InciWeb Incident Information System. Nov 10, 2009. <http://www.inciweb.org/incident/1856/>

Keeley, J. E. and Fotheringham, C. J. (2001), Historic Fire Regime in Southern California Shrublands. Conservation Biology, 15: 1536–1548.

Los Angeles(California). Watershed: Station Fire Recovery and Rehabilitation. Los Angeles & San Gabriel Rivers Watershed Council [2010].

Wonaschütz, A., Hersey, S.P.,  Sorooshian, A., Craven,  J. S.,  Metcalf, A. R., Flagan, R. C. and J. H. Seinfeld. 2011. Impact of a large wildfire on water-soluble organic aerosol in a major urban area: the 2009 Station Fire in Los Angeles County. Atmospheric Chemistry and Physics, 11 (16). pp. 8257-8270.

Archibald, S., Roy, D. P., Van Wilgen, B. W. and Scholes, R. J. 2009, What limits fire? An examination of drivers of burnt area in Southern Africa. Global Change Biology, 15: 613–630. 

Pringle, Paul. “Station fire's strength was miscalculated.” Los Angeles Times. Sept 27, 2009.