Fires, for many people, are a seasonal occurrence that becomes part of life. Southern California is one of these places. Every year in the fall, Santa Ana winds begin their annual march from the Great Basin and Mojave Deserts , across the heavily populated areas of Southern California and out to sea. These winds are a product of hot, dry air, expanding and ultimately creating a high air pressure system at the point in which they are conceived. This high pressure system is the ultimate source of the Santa Ana Pacific Ocean —they increase evapotranspiration of plant biomass as well as the land itself. This drying effect primes Southern California for intense infernos, which inevitably arise during this dry fall season. As with all prone natural disaster seasons (hurricanes, monsoons, blizzards, avalanches, etc…) the residents who reside in them must be vigilant, aware, respectful of the awe inspiring power withheld in Natures furious kinship to destruction.
Growing up in Lake Arrowhead , which is a small town in the San Bernardino Mountains of Southern California , I know the fire season all too well. Almost every year we would be evacuated from our homes, or at least threatened with the possibility of losing them. Generally this was no longer than a week in length, but at times, months; as with the Old Fire in 2003, which caused over 100,000 residents to vacate (Dunn). At the time of evacuation, for me, this was actually a very nice vacation from the all so dreaded days of high school. My family would stay with relatives whom lived near the beach, I would take it easy, and the best part of all is that we often did not have to make up school days later in the year because the events were usually christened “National Disasters” by the federal government. Understandably so, most saw this in a very different light, especially my parents, concerned with the loss of built property. However, the large concern for the community was always “what happens if the school burns down, where would everyone go?” Normally, in a city this isn’t a huge problem, just disburse the students into schools around the city until they can get some trailers in the Wal*Mart parking lot to house them for a little while…problem solved, right. However, in Lake Arrowhead San Bernardino
The fire that can be seen on the map above is the Station Fire. This fire began as a small blaze from a lightning strike in the Angeles National Forest Los Angeles history (Bloomekatz). This map shows the subtle complexities of the landscape on which the inferno roared. Topographic depth, urban populations, hospitals, school institutions, available nearby water from lakes and reservoirs, main roads and highways for access and evacuation are all shown in a single format, juxtaposed together, to maintain order and logic to the onlooker for maximum data comprehension and retention. These items were chosen specifically with the intent for planning and understanding how the fire progressed over time in relation to its surroundings. It is imperative to have fast, concise data that is accurate and easy to comprehend in emergency situations. Map making is as much about putting things on a map as it is taking them out; finding a balance is vital to creating useful cartographic data. I know all too well how important map data is; as an avid backpacker I use topographic trail maps to navigate through remote parts of wilderness areas. There have been many situations where I look to the map for quick reference, only needing minimal information, something that is easy to find on an uncluttered map. I have also been in very serious situations where time and decisions are critical for survival, also something that requires an easy to understand uncluttered map surface that also provides maximum information. This same rule applies to fire fighting and fire and forest management, as well as many other fields that require maps.
Schools were chosen to be placed onto this map for reasons stated above. For official who need to know what schools to close/evacuate, they first need to know what kind of danger particular schools are in. Data taken from the UCLA GIS data repository show where educational institutions exist in a geographic space, with respect to burn area and fire progression. There are many schools that neighbor the southwestern extent of the fires path, when counted there are about 56 sites that would definitely be considered as a fire prone area and one that is directly within the boundaries of the fire itself. This is useful for many reasons, but mostly as a means to see the whole picture, and what to do about it. The second data set (taken from the same source as the first) is hospitals. These are important for two major reasons. One, is that residents and officials may need to use them in the event humans are harmed by the blaze. The second is for hospitals within striking distance of the fire. These places may need to prepare for evacuation, something that would require quite a bit of planning and work to do properly. Hospitals also serve as a significant part of disaster planning, knowing where close ones are is critical for having spots for quick, useful help in emergency situations; something that wouldn’t want to be second guessed when the time comes to use them. Another part of this map that utilizes critical information is access roads. Knowing how to get people, vehicles, emergency personal and more into or out of an area is important to disaster logistics. Without proper preparation and execution this could become an Achilles’ heel to the development of a working plan; a scenario that has been seen in many hurricane zones and places alike. The next point of concern is where water is. Water is crucial to fire fighting; it has been for eons and will most likely continue to be for some time to come. In wildfires such as this, it is common to have super-lift crane helicopters drop thousands of gallons of water onto a blaze with intent to slow its progression. These helicopters ultimately want to have a large amount of water close by. Flight paths, aerial maneuvering, and many other aspects of “fire water” logistics would have to be planned out using a map such as this to better understand where everything exists within relation to the burn area itself. Though these items are important unto themselves, there is another factor to fire progression that reigns supreme, that is topography.
Topography is one of the main factors to why a fire does what it does. Fire inherently wants to climb up; hillsides, trees, wood, homes, anything that will burn. This, along with wind and rain, are very important factors to where a fire will go next and how long it might last. A digital elevation model, obtained from the National Map Seamless Server, was used to create a hillside topographic layout of the affected area. Upon this DEM was placed the fire progression polygon shape files, day by day. The information for the fire progression was obtained from the Los Angeles County Enterprise GIS data website, labeled as All Station Fire Perimeters. Combined, these data sets give a clear picture of how the fire might progress, or how it did progress, depending on what time you were/are looking at the map. It also gives onlookers a clear idea of how a fire might want to be fought. Forest wildfire fighting tactics are not hodgepodge procedural events; they are well planned, well coordinated, executed techniques, planned in advance (for the most part). Fire roads are built, breaks are made, water is dropped, men and women are stationed, and trucks are strategically located, all with containment of damage in mind. This would not be even close to possible with useful maps. Maps give clear reference to how and where a fire is progressing, and where high threat areas exists, such as schools, hospitals, and urbanized areas. These individual things may not be important on their own, but when layered with one another in a clear, concise fashion it creates a powerful tool for understanding the geography of a wild fire.
Works Cited
Bloomekatz, Ari B. "Station Fire Is Largest in L.A. County's Modern History."
Mapshare: UCLA's Spatial Data Repository. University of California, Los Angeles.
The National Map Seamless Server. USGS. Web. 20 May 2010.
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