Lab 7; Due 11/23/10

Chaparral, Landslides and The Station Fire

California is unique in that it contains almost every ecosystem in the world (aside from tropical ecosystems). Coastal Southern California is made up almost entirely of the chaparral (or Mediterranean) ecosystem, a shrubland characterized by hot, dry summers, cool, wet winters and high levels of endemism. Most importantly for this report, the chaparral ecosystem is specially adapted to fire. For example, plants have unusually high levels of oil in their leaves, helping them to burn quickly. Though this may seem counter intuitive, it helps to ensure the survival of the plant by not allowing the fire to get hot enough to burn its roots. The plant (say, sagebrush) then epicormically resprouts—it resprouts from its roots.

Because of chaparral’s pleasant climate (think San Diego, Italy, South Africa) it has been a coveted place to live for centuries. Unfortunately, chaparral people are not as adapted to fire as plants are. When fire season rolls around in late summer, when those Santa Ana winds kick in, and when lightning strikes on oil-laden sagebrush, fires spread rapidly and people don’t know how to handle it. Not only do they not know how to handle the fires themselves, but they don’t know how to cope with the after effects. They can’t just epicormically resprout, so to speak.

The Station Fire (8/26/2009-10/16/2009) started in Angeles National Forest and burned over 150,000 acres in Los Angeles County. Though the fire was started by arson and was not a result of natural processes, it nevertheless took advantage of chaparral’s ideal fuel conditions and ripped through LA, causing millions of dollars in damage, thousands to evacuate their homes and even loss of life.

Station Fire burn scar from Dave's Landslide Blog
(image originally from NASA) 

Of particular interest to this report are the ways in which the Station Fire affected soil integrity. When chaparral burns, the aforementioned oil present in Mediterranean vegetation wafts into the air, settles, and forms a water impermeable layer on the surface of the soil. This, coupled with the lack of vegetation to hold the soil in place, can create a very undesirable outcome when it rains: landslides. Landslides were especially threatening after the Station Fire because of the hilly topography that was razed.

Debris flow scars in the greater Los Angeles area
from (http://www.eoearth.org/article/Landslide)

In 2010, storm warnings for southern California threatened flooding and mudslides. In February, unexpected heavy rainfall hit La Canada Flintridge, which had been burnt by the Station Fire a few months prior. 43 homes were damaged by a “niagra falls” of mud that came rolling down from the burnt hills surrounding the area. Luckily no one was injured; this is mostly due to the evacuation orders mandated by the cities of La Canada-Flintridge, Sierra Madre, La Crescenta and Acton. These evacuation sites are depicted in the map below. Arroyo Seco also experienced significant debris flow, but as it is not populated it did not need to be evacuated.

Example of 2/2010 mudslide in La Crescenta from (http://i.cdn.turner.com/cnn/2010/US/weather/02/10/california.mudslides/t1larg.mudslide.gi.jpg)

The USGS has installed instruments around the Station Fire burn scar to monitor debris flow in those areas. These instruments measure rainfall, soil moisture, flow stage and bed pore pressure and are intended to “advance the understanding of post-fire runoff, erosion, and debris-flow generation processes and to provide information from the burned area to the National Weather Service for warning decision-making” (http://landslides.usgs.gov/monitoring/). There are three such sites in Southern California, two in Dunsmore Canyon and one in Arroyo Seco, and are demarcated on the map below. Directly below is an example of soil moisture and rainfall data collection from http://landslides.usgs.gov/monitoring/.

Southern California’s Mediterranean/chaparral ecosystem is attractive to settlers because of its exceptionally mild climate characterized by hot, dry summers and cool, wet winters. However, chaparral is also very prone to fire; after an area burns it is also very prone to landslides. People are tying to adapt to these natural disasters, but evacuations are sometimes the only way in which to ensure safety. We are continually advancing our knowledge through monitoring sites and scientific data collection, and perhaps we will be better able to cope with fire (and landslides) in the future.

Bibliography

Landslide Hazards Program. Web. 20 Nov. 2010. (http://landslides.usgs.gov/).

"Landslide." Encyclopedia of Earth. Web. 20 Nov. 2010. (http://www.eoearth.org/article/Landslide).

"Latest Storm Prompts Evacuations for Station Fire Burn Areas | 89.3 KPCC." KPCC. Web. 20 Nov. 2010. (http://www.scpr.org/news/2010/02/19/storm-friday/).

"Malibu Surfside News: Rambla Pacifico Is Closed by Landslide." Malibu Surfside News. Web. 20 Nov. 2010. (http://malibusurfsidenews.com/blog/2010/02/rambla-pacifico-is-closed-by-landslide.html).

"Mudslides Occur in the Areas Affected by the 2009 Station Fire in Los Angeles." Dave's Landslide Blog. Web. 20 Nov. 2010. (http://daveslandslideblog.blogspot.com/2010/02/mudslides-occur-in-areas-affected-by.html).

"Mudslides Threaten California Hillside Communities After Station Fire | AHN." All Headline News. Web. 20 Nov. 2010. (http://www.allheadlinenews.com/articles/7016614039?

Mudslides%20Threaten%20California%20Hillside%20Communities%20After%20Station%20Fire).

"'Niagara' of Mud Hits Homes." Featured Articles From The Los Angeles Times. Web. 20 Nov. 2010. (http://articles.latimes.com/2010/feb/07/local/la-me-rain7-2010feb07).

Lab 6; Due 11/16/10

I chose an area in eastern Tennessee to focus my DEM on. The Appalachians are notorious for their strange formations, and thus I thought they would produce an interesting model. I kept the same color scheme for each map in order to maintain uniformity. The extent of my data can be understood as having corners at N 35.40965, S 34.95264, W -83.97316 and E -83.44494. Also, there is a 50% transparency for the Shaded Relief Model map.

The final product--a 3D depiction of my data.

Lab 5; Due 11/9/10

Map projection is the process by which a three dimensional datum is "projected", or shown, on a two dimensional surface. There are three surfaces onto which a map can be projected: the cone, the cylinder and the plane. Each of these projections has a certain amount of (unique) distortion; to save certain relationships between area, distance or angles one must sacrifice other relationships. Here I will denote the significance, perils and potential of (the below) map projections. First I will explain them and discuss their significance. Then I will move into the perils of projections, finally ending on a positive note with their potential. 

The two below Mercator maps are examples of conformal projection, which preserves angles locally. This is important if one is navigating by sea or air and needs to keep a standard bearing on the land. The two below equidistant projections preserve distance. That is, they preserve the integrity of distance from one standard point or line. Obviously, this is good for knowing exactly how far away places are. The reason Washington D.C. and Kabul are different distances apart in my two equidistant projections is because one measurement runs across the Atlantic while the other runs across the Pacific. My final two maps preserve area, that is, the map images are proportional to the area of the landforms which they represent. 

The perils of map projection are great. As I mentioned earlier, no map is able to preserve every relationship and must instead sacrifice the integrity of some relationships for others. You'll notice that in the Mercator Projection, Greenland is huge. (It's even bigger than Australia.) If you then look at either of the two Equal Area projections, you'll notice that Greenland looks much smaller. This is because in the "equal area" projection, area is preserved. On the other hand, if one attempts to navigate angles with an equal area map, it will be very difficult to succeed. (The conformal projection should instead be used in this case.) When choosing a map projection, one has to take into account what the map will be used for, and choose the projection accordingly. Otherwise you could end up in Sudan when you really wanted to hit Kenya.  

The potential of map projections is infinite. There are countless ways in which to represent the world datum, and if you know what you're doing, you could personalize a map projection to meet your specific needs. 50% distance, 25% angles, 25% area? There must be a projection for that. Navigating? Use this one. Making a topo? Use another one. Learning the countries in Africa? Use this one. Want to inflate the importance of Greenland? Use that one. Projection has the potential to enhance any set of research, or aid in any travel, or really accomplish any spatial goal. (One can even manipulate projections to show a specific point of view.) As we grow in our map knowledge, perhaps there will be some all-encompassing map, able to preserve every relationship phenomenally. In fact, I'm almost positive there will be a map like this some day. Until then, we need to choose a projection very carefully.