Monday, March 18, 2013

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.

Thursday, February 28, 2013

Assignment 7: Census Maps

I created three population maps this week from census data from 2000.  I decided to try out different map layouts to see how each looked.
 
The Black population map in the United States can be seen above.  The Black population is clearly the largest in the Southeast.  This comes from pre-Civil War era where the high concentration of African slaves was in the South working on plantations.  Much of these Black populations did not migrate far, and so have remained in the Southeastern United States in high percentages.  There is also a higher percentage of Black population in California, known for being more diverse and generally have higher minority percentages.  Also it is interesting to note that in more recent years, the black population growth rate for the black population "surpasses U.S. average" according to an article in the Business Journals, an online news site.
 The Asian population is very heavily represented on either coast, at most often urban centers.  The west coast is particularly dense because the ports in the West are were many Asian immigrants arrived.  These populations often arrive in the United States from this direction and have been migrating out from these areas since.  It is also noteworthy that the highest percent population was around 46%, indicating that there are not any particular counties that have an incredibly high percentage of Asians.  Likewise, in the whole country, it can be seen that the percentage of Asian population is rather low in most states not located on the West Coast.  It is interesting to note that the Asian populations in the last ten years has grown considerably, tending to very between 40-80% growth every year, according to an article written based on the 2010 census.

 Other races distribution can be seen heavily influenced by the Hispanic populations.  It can easily be seen that all of the states bordering Mexico have the highest percentages of other races.  This is most likely immigrants from Mexico, Central America and South America that are arriving in the border states such as Texas and California.  This is why these counties have the highest percentage.  In the North, a small amount of immigrants that come through Canada can be identified around the Washington area.  Also, most likely from Caribbeans, there are some higher concentrations seen in some parts of Florida.  Overall, the Mideast and Northeast have very tiny percentages.

This map series provides very interesting perspective on the percentage populations of different regions throughout the U.S.  In fact, a quick slideshow where the maps are aligned could quickly give an idea of the overall distribution of populations in the United States.  After reviewing the maps I created, I have concluded that I believe the third map is the most visually appealing.  The blue background and varied, but intense colors used as identifiers makes it stand out among the other two.  It is also important to note how effective at ArcGIS was at helping to create these maps.  Joining data from tables can be incredibly powerful, as there is a lot of data collected in table format not necessarily for maps, but with ArcGIS, they can be used to create maps by importing them and joining them to the geographical data we have already collected.

Reference:
1. "Growth rate for black populations", Thomas, Scott. Business Journals. <http://www.bizjournals.com/bizjournals/on-numbers/scott-thomas/2012/10/growth-rate-for-black-population.html?page=all>
2. Campbell Gibson; Kay Jung (September 2002). "Historical Census Statistics on Population Totals By Race, 1790 to 1990, and By Hispanic Origin, 1970 to 1990, For The United States, Regions, Divisions, and States". Population Division. United States Census Bureau. Retrieved 17 November 2012.

Thursday, February 21, 2013

Assignment 6: DEMs in ArcGIS





The spatial extent information for this map:
Top: 39.8291666661
Left: -105.788888889
Right: -104.969444445
Bottom: 39.3838888883

Spatial Reference: GCS_North_American_1983

Saturday, February 16, 2013

Assignment 5: Projections in ArcGIS

This week we examined different map projections in ArcGIS.  Six different projections can be seen below:





  Map projections are incredibly powerful and important when considering a map, especially when considering the world.  The larger an area a map covers, the more distortion there can be between the real world terrain and the map.  This is because the world is naturally curved, but a map is flat, so we must use projections to force the three dimensional terrain fit on to a flat surface.  Each projection brings different distortions about distances, areas and relative measurements we might make on the map.  It is important to know that each map projection will often have different measurements for distance, area and relative sizes, and each of these may be different from the real 3-d values.  This can clearly be seen by comparing the different values of measured differences from each map, the variation is very great and none of them represent the actual on surface distance between Kabul and Washington D.C..
  This becomes one of the greatest perils of map projections; the improper use or knowledge will easily lead to false measurements.  When comparing measurements about landmass or distance, it is easy without proper understanding of projections, to use the incorrect one.  This will lead to incorrect data that might lead to incorrect conclusions.  The major pitfall is that most of us use maps with an assumption of scale.  Although many maps use exaggeration, when we for instance view a world map, many often assume that all the proportions are to scale.  The Hammer projection is something that we are used to, but this projection doesn't preserve distances, but most would easily assume they can measure the distance between two cities based on this projection.  And although looking at the Mercator projection, it may almost seem obvious that the sizes are incorrect when viewing it with latitude and longitude, without these values and a slight squishing of the ends of the map, it becomes a very commonplace map.  This map is not accurate in size or distance and can easily give us a skewed view of comparisons. 
  Many of the projections feel unnatural because we don't see them often.  This can easily cause the average user problems because a map projection like azimuthal equidistant feels strange.  However it is maintaining relative distances, and really all map projections should feel strange because we are seeing all sides of a three dimensional object in a plane.  The map projections are almost by nature illogical because they cannot actually represent how the globe looks from any real world angle.  This can be seen with the Stereographic, when following the latitude lines, a much more accurate measurement of distance can be observed, but it also makes it very apparent that we are seeing both the top of the globe and bottom simultaneously, causing us additional natural confusion.
  These perils all however show how important using map projections correctly can be.  It demonstrates that using these projections correctly can be very powerful.  For example, if we disregard our initial odd feeling about sinusoidal, it gives us such a more accurate picture of how to compare how wide Antarctica is compared to Africa.  The distance between parallel meridians is preserved, and normally it is very hard to determine these distances accurately.  But now in this projection we can get a much more accurate picture, it reveals a lot about the usual map projections we use and how distorted they are.  Viewing a map that covers a large area in different projections reveals much more information and accuracy than viewing it in a single projection.  Map projections can help reveal the truth about the geography of these areas.

Thursday, February 7, 2013

Assignment 4: Introducing ArcMap

The ArcMap tutorial produced a poster about proposed airport expansion.


I found the ArcMap tutorial very interesting.  The process of going through all these tools really revealed how powerful a GIS system can be.  I thought there were many points where I could see many additional uses for the functionality we were learning.  For example, the population density that was retrieved from a table and joined based on ID was extremely powerful.  It made showing very numerical and hard to visualize data on a map incredibly easy because the computer would map the colors and pair the correct population values with each region.  This long tutorial also made me appreciate the complexity and challenge of such an advanced GIS system.

This GIS system had incredible functionality and many uses.  GIS is able to make a strong translation between data and visuals.  This is incredibly important as it is hard for many of us to comprehend purely data driven presentations such as tables and calculations.  A map or visualization of data is often critical to our understanding and ArcMap really helps make this possible.  GIS can transform powerful data sets and months of research into a presentable form.  The maps created out of these GIS systems are incredibly diverse, as the tools are rich and complex.  A map can be made for any purpose with the ubiquity of GIS.

The drawback is complexity with GIS systems.  Even through several hours of tutorial, it can be easily seen that this amount of complex creation of maps is time consuming.  The users of GIS that understand it completely must still work for many hours to produce a final result.  This is a major improvement over old mapping techniques however, where the many hours would still result in discrepancies between data and the final map.  Here at least, GIS keeps track of the data carefully, and the resulting map will always be drawn according to the data you desire.

Overall, I feel GIS systems are extremely powerful and beneficial.  The power of computing is becoming increasingly important in the modern age, and I think GIS is a crucial step in harnessing that power to visualize and show data.  More and more data is becoming available as we integrate computers into our everyday lives.  With this quantity of information, it is important to have tools like GIS that can decode, display and quantify it.  The incredible power of GIS is that so much computation can be done through computers, leaving us to think about the higher abstract concepts and ramifications of results rather than having to focus solely on computation and analysis.  I think GIS is the only way forward in a data heavy world.

Thursday, January 24, 2013

Week 3: Neogeography

I created a map to identify the places I've been to that mean the most to me.  I marked and described the most memorable locations in the world that I've been to in my life.

View Most Memorable Places in the World in a larger map

Neogeography is an amazing tool, but it has potential pitfalls too.  One of the biggest dangers is inaccuracy of information.  When so much of the information that goes into these online maps are purely user created, it is hard to tell the accuracy of such maps.  There is a distinct lack of checking and editing on user-created maps, so it is easy to be fooled.  In addition, there are dangers to sharing too much personal information.  If an individual shares their daily walking route to work, that person is easily vulnerable to the invasion of privacy.  Even something as simple as sharing the locations of all your favorite bars could be viewed by potential employers that might wonder if you go out to drink too often.

However, these concerns aside, it is incredibly powerful.  When talking about inaccuracy, consider that often times there was no offering of this information before.  It is often better to have an inaccurate map then none at all.  Neogeography allows users to share real experiences in a much stronger way, emphasized by their customizations and added details.

I think the future will be a neogeographic world.  I believe that the maps that everyone uses will be made by other normal users.  A review-based ranking like ratings on Youtube or likes on Facebook will most likely help users identify which can be trusted and which to avoid.  The ubiquity will be in your device all the time; simply by asking your phone you will be able to find any store, location or spot you want.  I think it's likely we will most likely be viewing photos and videos that relate to our physical location everywhere we go.  I think neogeography is only going to become more widespread and powerful in the years to come.

Thursday, January 17, 2013

Week 2: Map Anatomy

 A 7.5 Minute Map of Beverly Hills
Figure 1. Nearby quadrangles
1. What is the name of the quadrangle?
 The quadrangle is entitled the Beverley Hills Quadrangle

2.  What are the names of the adjacent quadrangles?
There are 8 nearby quadrangles, as can be seen in Figure 1.  The immediately adjacent quadrangles are Van Nuys, Topanga, Hollywood and Venice.  The names of the quadrangles found diagonally can be found in the figure, though the quadrangle to the Southwest appears to be unnamed.

3. When was the quadrangle first created?
The earliest creation date on the map was 1966.

4. What datum was used to create your map?

The vertical datum used was the vertical datum of 1929.  The two horizontal datum were the datum of 1927 and the datum of 1983.

5. What is the scale of the map?
The scale of the map is 1:24,000.

6. At the above scale, answer the following:

a) 5 centimeters on the map is equivalent to how many meters on the ground?
5 centimeters = 120,000 centimeters on the ground = 1200 meters on the ground
b) 5 inches on the map is equivalent to how many miles on the ground?
5 inches = 120,000 inches on the ground = 1.89394 miles on the ground
c) one mile on the ground is equivalent to how many inches on the map?
one mile = 63360 inches on the ground = 2.64 inches on the map
d) three kilometers on the ground is equivalent to how many centimeters on the map?
3 kilometers = 300000 centimeters on the ground = 12.5 centimeters on the map

7. What is the contour interval on your map?
The contour interval is 20 feet.

8. What are the approximate geographic coordinates in both degrees/minutes/seconds and decimal degrees of:
a) the Public Affairs Building;

Approximately 118°26'15'' E   34°4'30'' N
or  118.4375° E   34.075° N

b) the tip of Santa Monica pier;
Approximately 118°29'45'' E   34°0'30'' N
or  118.4958° E   34.0833° N
c) the Upper Franklin Canyon Reservoir;
Approximately 118°24'45'' E  34°7'15'' N
or  118.4125° E   34.1208° N

9. What is the approximate elevation in both feet and meters of:
a) Greystone Mansion (in Greystone Park);

About 540 ft or 164.592 meters
b) Woodlawn Cemetery;
About 140 ft or 42.672 meters
c) Crestwood Hills Park;
About 620 ft or 188.976 meters

10. What is the UTM zone of the map?

The UTM zone is zone 11.

11. What are the UTM coordinates for the lower left corner of your map?

The UTM coordinates in the lower corner are 3763000mN and 3762000mE.

12. How many square meters are contained within each cell (square) of the UTM gridlines?

1,000,000 square meters.  The side of each UTM grid square is 1000 meters.

13. Obtain elevation measurements, from west to east along the UTM northing 3771000, where the eastings of the UTM grid intersect the northing. Create an elevation profile using these measurements in Excel .


14. What is the magnetic declination of the map?

The magnetic declination is 14°

15. In which direction does water flow in the intermittent stream between the 405 freeway and Stone Canyon Reservoir?

The stream flows South.

16. Crop out (i.e., cut and paste) UCLA from the map and include it as a graphic on your blog.

The part of the map showing the UCLA campus