The first map is a reference map that shows the relative location of the area affected by the fire. It also shows the extent of the fire on the final day. The area shown is the largest that could be successfully downloaded from the USGS website. This is because anything more was over the allotted 1500 MB. If it was possible to download more content, I would have chosen to portray the location of the fire as a small polygon within the State of California. The second map is thematic map that shows cities and lake locations relative to the spread of the fire. Finally the third map shows the aspect of terrain around the area being examined.
During the year 2009 there were a total of 63 fires in California, burning a total of 336,020 acres. The worst of these was the “Station Fire” which accounted for over half of the total acres at 160,577 acres. This fire began on August 26th 2009 and the perimeter was not completely contained until October 16th 2009. This is an average of over 3000 acres per day, which is more than most fires burn during their entire existence.
As is shown on the reference map, figure one, this fire is located in the hills above Los Angeles. There are three aspects that will be discussed in the following paragraphs. These are location of lakes, locations of cities, and slope of mountains with respect to fire spread. Before the spatial analysis was performed it was hypothesized that one would observe the most fire spread in the direction away from both cities and lakes.
First, it needs to be noted that the nearest lakes are located south of the location of the origin of the fire. Thus, one would expect the fire to propagate further to the north. These are the expected results because one would expect that the areas that are closer to the lakes would get doused with water more often than those locations further away from them. When looking at the second figure it is clear that this is what has happened. The yellow polygon located in figure two represents an area in which the fire originated. One can clearly see that there are three lakes located relatively close to this location. Based at the legend presented at the bottom of the map, one can see that as time progressed so did the extent of the fire. Over a four day period the fire propagated nearly twenty-five kilometers outward, toward the north. This occurred between 5 degrees and 165 degrees as is portrayed in figure two. One of the main criticisms of the fire department was that they did not begin using water soon enough, which allowed the fire to become too large to control (Saillant).
Next, it was noted that the fire originated above a large density of cities. One would expect that the fire department would do everything possible to keep the fire from going towards the heavily populated areas. The reason one would desire to keep the fire from cities is to protect homes as well as lives. It can be seen from figure two, the thematic map, that the fire was forced away from major cities and highways into the mountains. This ended up destroying much more land, however, there were only 2 lives lost during the fire. In addition to this there were also 22 injuries (Station fire).
Examining figure three it becomes clear that once the fire made it over the top of the mountain, closest to the point of origin, the expansion of the fire increased exponentially. And because the fire was off the roads, in very rugged terrain, it made it impossible to stop. This is why when one examines figures one and two simultaneously it can be seen that the day after the fire makes it over the ridge there is the most growth area that the fire has engulfed. It is actually very interesting to compare the aspect map to the fire propagation map. This is because when examining them side by side it can be seen that the fire gets trapped between the ridges of the mountains. When examining how the fire spread on different days it seemed as if the fire fighters conceded the entire valley and set up “defenses” on the ridges, however, this is merely speculation.
The hypothesis was proved correct. It was shown that the fire was indeed “lead” away from the populated areas. It was also fended off by the lakes and was allowed to traverse the mountain. These combined saved many lives, however, much vegitation was destroyed. Finally, based on the amount of growth each day along with the fires position on those days, it was discovered that the fire spread faster as it went into the valley. This may be due a number of factors that include: wind through the canyon, vegetation, lack of population, and lack of accessibility. It did seem that the fire was stopped at the top of each of the ridges which leads one to believe that the fire men may have dug trenches or set up “controlled burns” in order to stop the fires here.
Citations
"Census Cartographic Boundary Files." Los Angeles County GIS Data Portal.County of Los Angeles, 011. Web. 08 June 2011. http://egis3.lacounty.gov/dataportal/?p=1048.
Martin, Mark. "Station Fire Burn Area: Two Years Later." Los Angeles Times, 14 Apr. 2011. Web. 07 June 2011. http://framework.latimes.com/2011/04/14/station-fire-burn-area/#/0.
Nester, Irene. "The Station Wildfire." Burn Severity Map of the 2009 Station Wildfire in Southern California. Emporia State University, 10 Dec. 2009. Web. 7 June 2011. http://www.emporia.edu/earthsci/student/nester4/fire.html.
Saillant, Catherine. "Delays on Additions to Forest Service's Firefighting Fleet Unacceptable, Sen. Dianne Feinstein Says." Los Angeles Times, 21 May 2011. Web. 07 June 2011.
http://www.latimes.com/news/local/la-me-station-fire-20110521,0,7290556.story.
“Station Fire.” InciWeb the Incident Information System. 10 Nov. 2009. Web. 07 June 2011.
http://www.inciweb.org/incident/1856/.
“The National Map Seamless Server Viewer." USGS. Seamless Data. U.S. Geological Survey, 28 Dec. 2010. Web. 08 June 2011. http://seamless.usgs.gov/website/seamless/viewer.htm.
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