Week 9 Lab 8

For this Final Lab I looked at the relationship between fuel type as classified by the California government fire division and the topography of the Los Angeles Station fire in order to understand the nature of the fires expansion. The fire started in the Angeles National forest and burned between august 26 and October 16th 2009. A total of 206 buildings were destroyed including 89 homes and two firefighters were killed when their car were flipped over and fell off a cliff while they trying to escape a dangerous area. The blaze threatened the nearby communities of La Canada, Flintride, Glendale, Acton and La Crescenta. Many areas faced mandatory evacuation but these orders were removed by the 6th of September, as much of the fire climbed up the slopes of mount Whitney away from the city.

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In order to asses the posibility of fires the California Department of Forestry and Fire Protection has create a system for ranking fuel. The fuel ranking methodology assigns ranks based upon the way fire is expected to behave through a combination of topography and vegetation fuels under severe weather conditions including wind speed, humidity, and temperature. Initially fuel rank is culated through a combination of the fuel model plus the slope of the area. The Surface rank is then combine with the Ladder Index and the Crown Index to determine the fuel rank. The fuel rank is categorised in 4 different levels: zero being that the area is unlikely to burn, is an impervious surface or water, one has a moderate chance, two has a high chance, and three has a very high chance of burning.

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There are many types of flora and fauna in the San Gabriel mountains with a combination of conifer and broad leaf forests making the area fall under the timber group for estimating fire behavior, more specifically group ten. This group is comprised of forests with lots of dead dry fuels such as pine needles and fallen branches. It also includes windblown stands and over mature situations with dead fall, both of which are aspects of the Angeles national forest.The fire was difficult to maintain because model ten forest tend to fall within the upper limit of control and direct attack, combined with a dry summer and high winds made containment exponentially more difficult.The conditions along with the lack of road access in the mountains meant that once the fire was no longer a threat to the city it was left to burn itself out and was not fully extinguished until a light rain on the 16th of October. Compared to other large fires throughout Californians History the Los Angele station fire was the worst in the counties history.

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As the fire moved north through the the San Gabriel Mountain it moved quickly along the ridge lines of the hills while the valleys took longer to be consumed. Due to the nature of fire, it moves much faster on sleeper positive inclines as the heat rises and the tips of the flames reach further up the hill. This factor proved very beneficial in the Los Angeles Station fire through a combination of increasing elevation away from the nearby communities as well as the winds coming off the pacific ocean. This pushed the fire northeast up into the mountains and made it difficult for the fire to burn down towards the city. However many citizens complained that the fire could have been subdued within the first 48 hours before it was able to expand rapidly and escape the fire fighters control. This was unable to be accomplished due to the nature of the area. 

The Los Angeles Station fire devastated the natural landscape of the Angeles National forest but luckily due to advantages in topography, predictions based on fuel rank, and climate conditions, the fire spread to the north and northeast, away from the urban centers of Los Angeles and the downtown. However this does not exclude the work of firefighters who did the very important job of initially stopping the fire from spreading south which would have happened, at a slower pace due to wind, poor fuel, and level ground, if their was no intervention. Thank you Lisa, It has been a great class and I have learned a lot.



Sources

Anderson, Hal E. Aids to Determining fuel Models for Estimating Fire Behavior. Ogden, UT: United

States Department of Agriculture, 1982. http://www.fs.fed.us/rm/pubs_int/int_gtr122.pdf (accessed

December 10, 2012). 

Ca.gov. "fuel ranking maps and data." Californian department of forestry and fire protection

http://frap.cdf.ca.gov/data/fire_data/fuel_rank/index.html

Pringle, Paul. "House panel presses for answers on station fire." Los Angeles Times. 

http://articles.latimes.com/2010/oct/13/local/la-me-station-fire-20101013 (accessed December 10, 

2012).

Shagun, Louis. "restoration not taking hold in land burned by station fire." Los Angeles Times. http://articles.latimes.com/2012/apr/07/local/la-me-dead-trees-20120408 (accessed December 10, 2012).

"wilderness and rivers." San Gabriel Mountains Forever.

http://www.sangabrielmountains.org/wilderness_and_rivers (accessed December 10, 2012).

Images
http://eoimages.gsfc.nasa.gov/images/imagerecords/40000/40115/calif_msr_2009242.jpg