Lab 7: Census 2000/2010

        This map above shows the population density in 2000 from the U.S. Census Bureau's Census data. This chloropleth map shows graduations of population change from low to high populations throughout the United States. The darker blue and darker green colors have higher population densities, whereas the lighter green colors have increasingly lower population densities. The different colors make it very easy to spot the largest clusters of people, like in the Northwestern United States (Southern California) and along the East Coast. This color scheme also allows us to see where populations are the most sparse, like Oregon, Nevada and other Western states.  

       The map above, titled "Number of People, 2000" illustrates the number of people living throughout the United States. Instead of shades of green and blue, this map utilizes gradations of purple, with darker purple indicating larger numbers of people and increasingly lighter people indicating increasingly smaller numbers of people in different counties. This gives another perspective on where people are located, because there are areas that have significantly higher populations but aren't necessarily dense because there is more land where people tend to spread out and disperse, instead of cluster (as shown in the previous map, "Population Density, 2000").

       The above map, titled "Percent Change, 1996-2000 Total Population" shows how much the population in certain counties increased or decreased between the years 1996 and 2000. This chloropleth map shows the darker purples as having positive increases, with increasingly lighter purple having lower positive increases. This purpled then transitions into pink, which basically shows little to no increases. Then the pink transitions into yellows and oranges which indicates decreases in population percentages. As you can see by the map, there seems to be a large increase in percent population in counties in Nevada. There also seems to be big decreases in population change in a line down the central United States. 

       This last map, "Difference, 1990-2000 Number of People" illustrates the difference in the number of people between the years 1990 and 2000. This map illustrates the how much the number of how many people in each county has changed, instead of a percentage change (as in the previous map). Dark pink indicates there is a negative change in number of people. Light pink indicates a slight negative change in difference in the number of people in different counties. All of the green colors indicate increases in the number of people per county. The darker the green, the higher the increase of number of people in each county is. 

       Mapping the Census Data using GIS was very helpful for understanding how versatile the census data is and the diversity of options there is to create maps and analyze the data using GIS. It's really quite amazing how much Census data is available and the data can basically be transformed using maps to convey and illustrate the data to anyone who views the map. Even though the data about population might seem similar at first, when it is visually represented on the map it is clear that all these different data sets have different geographic implications. 

       Overall, this map series exercise showed me how GIS can be seen as a little complicated at first, but once you keep using it, the program becomes easier and more natural to use. I am very impressed at all the functions GIS has to create the different chloropleth colors (gradations of colors) automatically and also how it was so easy to integrate the U.S. Census data into the program. Thus far, I have a very positive impression of GIS, especially with this project, as using the data to create the map series really represented how versatile the software is and the flexibility there is in showing different types of spatial information on a map to illustrate different geographic phenomena. 

Lab 6: DEMs in ArcGIS

Hillshade Layer

Slope Layer

Aspect Layer

DEM Arc Scene (3D)

       For this week's lab, we created D.E.M.s (Digital Elevation Models) using the DEM data from the class website. The extent for this data is 39.8292 decimal degrees for the top, -105.7889 decimal degrees for the left, -104.9694 decimal degrees for the right and 39.3839 decimal degrees for the bottom. The coordinate system used was the North American Global Coordinate System from 1983. The hillshade layer shows the relief and terrain in this area. The slope layer shows the degree and intensity of the angle of the slope in this region. The aspect layer shows the directionality of the terrain. The DEM shows all the data in a three-dimensional model.

Lab 5: Projections in ArcGIS

       For this week's lab, we compared the distance of two cities Washington D.C. and Kabul between different map projections in order to see how much these differences differed depending on the map projection. We utilized two equal area projections, two equidistant projections and two conformal projections. As you can see when referring to these different map projections, the appearance, shape, and distortions of each of the maps differ depending on the the type of map projection (conformal, equidistant or equal area) it is and even the specific map projection the map is made from. For example, the equidistant conic looks significantly different than the Hotine, both in the representation of the entire earth and the way the continents are arranged on the map. This is significant for map makers and map users because it is an obvious display of how map projections can make earth's surface look distinctly different and can impact the way we utilize maps. Taking into consideration which projections distort and preserve certain features (area, distance, shape, etc.) is essential to creating an appropriate map. These maps also show that there is always a distortion, no matter what type of map projection that you use, so knowing the map projection you use is critical and significant for keeping all the datums that you use consistent.

       The perils of map projections mainly stem from the distortions that are inherent in each type of map projection. As you can see below each of the projections, the distance measured between the two cities mapped (Washington D.C. and Kabul) on each projection is very inconsistent. None of the measured distances match up between any of the projections. These measurements differ by more than a thousand miles when comparing the equidistant conic and the azimuthal equidistant maps (which preserve distance)! These data inconsistencies can become a big issue if you are collaborating with someone else and both parties are using different map projections. It can also be an issue when inputting data from one projection into a map with a different map projection.

      The potential of map projections include highlighting certain properties and preserving specific factors in order to get the three dimensional surface of the earth on a two dimensional map. Also, map projection potential includes having the earth portrayed on a flat surface. As it's impossible to get earth on a two dimensional surface without distortion, having different types of map projections are extremely important because different map projections will allow the map user and anyone analyzing the map to have confidence in certain aspects of the map projection and compensate for a lack of accuracy in other aspects of the map created from particular map projections. For example, map users, cartographers and map analyzers can have confidence in the sinusoidal (an equal area map) to accurately portray equal area, but they will understand that these maps may not be completely accurate in terms of distance or shape. The variety of these different projections allow cartographers to choose different projections that will appropriately fit their needs.

       Overall, projections are extremely important in cartography and ArcGIS use. Projections are essential to create a three dimensional image on a two dimensional surfaced. Despite their distortions, the variety of projections allow cartographers and GIS users to choose the appropriate projections that will enable the map to portray what they need. It is extremely important that people using GIS understand which projection they are using so they can compensate for and understand the distortions and inaccuracies inherent within that map projection.

Equal-Area Projections: Eckert VI & Sinusoidal

Eckert VI
Distance: 7,551 miles.

Sinusoidal

Miles: 8,276 miles.

Equidistant Projections: Equidistant Conic & Azimuthal Equidistant

Equidistant Conic
Distance: 7,118 miles.

Azimuthal Equidistant
Distance: 8,419 miles.

Conformal Projections: Hotine & Stereographic

Hotine
Distance: 7,053 miles.

Stereographic
Distance: 9,814 miles.

     

Lab 4: Introducting ArcMap

Exercise 1: School and Noise Contour Map

Exercise 2: Land Use in Noise Contour

Exercise 3: Population Density

Exercise 4: Adding a New Road

Exercise 5: Adding Map Elements/Putting it All Together!

       For our fourth lab, I got to start using the ArcGIS software to make a few maps through a tutorial in class. The tutorial made it very straightforward to go through the steps and it illustrated the applicability the GIS tool is to many everyday urban planning issues, like planning airports with the integration of noise, population and school data. Using the software by following the tutorial step by step was very easy, but I am not sure if I would be able to use the software with ease if I did not have a guide. However, with practice and greater familiarity, I am sure the ease-of-use will improve gradually.

       From my experience with this lab and map-making tutorial with ArcGIS, I would say that the "pros" of the software are that it is fairly user-friendly with the use of a tutorial guide. In addition, some of the labels and buttons are very similar to many regular computer users (i.e. selection boxes, pointer arrows, zoom in, zoom out, etc.) so it is relatively easy to apply some of the common use of the tools to the different applications within the software. I also thought it was very easy and helpful to turn certain layers on and off, depending on what variables you needed to see/not see. For the fourth exercise, turning off certain layers and omitting certain data layers was actually helpful to just see what I needed to see (the roads) in order to create the new road on the map. It might have been confusing to have every layer turned on, so those features were really helpful. In general, the potential of GIS using ArcGIS is very beneficial and powerful, as it is fairly easy to use when making basic maps, like the ones we completed in our lab. Additionally, there is so much information that can be applied to the maps that the possibilities are endless. 

       There are a few pitfalls of this GIS software, which were a bit frustrating at times. For example, I had to redo some of my maps because my data randomly disappeared. I figured out how to get some of it back, but then sometimes the data just didn't ever come back so I had to restart my exercise from my last saved file. For these problems, it's really hard to pinpoint the causes of the issues and how to fix it. I can see where it can be very easy to lose important data or important maps if you are not constantly backing up. With any software, especially one that is as data-driven as GIS is, saving is especially important. I also felt as if the software might be overwhelming for some users at first, because there is a LOT of buttons and icons. It would literally be impossible for a new user to know exactly what to do if they did not use a guide or tutorial. In other words, icons that don't look like common computer icons (i.e. zoom in, zoom out, selection boxes, etc.) are not intuitive. I also noticed that there were a lot of changes on our instruction to the way the program worked, which means that the software gets updated frequently. In some ways, this is good, because problems in the software can be resolved but it also means that the user will constantly have to adjust to new changes. Overall, the main pitfalls of the software would be that it's not really intuitive (like Google Maps), so the average person might not be able to use this software right away if they didn't use a tutorial or a guide. Additionally, there are a few bugs in the software that I found to be frustrating in my short exposure to the program. Lastly, another pitfall could be the way the software has periodic changes which can be difficult to adjust to.

       I think GIS is a very versatile and powerful program that literally can map anything imaginable. I think once exposed to the program through a tutorial, the program is very accessible and easy to approach. However, for an average computer user, this program might not be as easy to use as Google maps and may be confusing to figure out how to operate the program. All things considered, GIS is great for high volume of data and sophisticated maps for urban planning, business research and development, conservation efforts and so much more. I really think it is meant more for professional use (geographers, urban planners, architects, engineers, etc.) more so than for the average person.