Lab 7 - Mapping the Station Fire in ArcGIS

Lab 6 - DEMS in ArcGIS

After acquiring DEM data from the USGS website, I created a set of maps of the Grand Canyon in Arizona. I chose this famous historic site because of its dramatic and intricate elevation changes. Carved by the Colorado River, the Grand Canyon extends 277 miles and boasts areas as wide as 18 miles and deeper than a mile. Most of the area lies within the Grand Canyon National Park, which helps preserve its rich geological history and diversity of species. As an extensive rift in the Colorado Plateau that contains Proterozoic and Paleozoic layers, any section of the Grand Canyon is sure to produce a unique Digital Elevation Model. The slope of the area I selected remains fixed for the most part, thus producing a virtually single-colored map. However, the other 3 maps proved visually stunning, reflecting the impressive landscape of the Grand Canyon and the flowing Colorado River.

Extent information:
N: 36.47169*
W: -112.15541*
S: 35.98538*
E: -111.74667*

Geographic Spatial Coordinate System:
GCS North American 1983

Grand Canyon, Arizona
3D Elevation Model

Lab 5 - Projections in ArcGIS

Map projections allow us to view the world on flat, portable surfaces like a piece of paper, and on the computer screen using digital map data. Since the Earth is more or less a 3-D sphere, projections are key in translating the world into a more practical 2-D format. The Earth can be represented at various scales depending on the type of projection. Consequently, the three-dimensional Earth can be observed and analyzed from different perspectives and in appropriate detail.

Perils of map projections predominantly lie in their inevitable distortions. Map projections using different developable surfaces, such as planes, cones, and cylinders, produce various distortions. As we transfer information from the real world to a virtual map, projections distort the shape, area, distance, and/or direction of the Earth. For example, the maps below show significant variance in distance between Washington, D.C. and Kabul, Afghanistan based on the projections used. Thus, mapmakers and readers must be wary of the map’s scale and purpose when choosing an appropriate projection.

Map projections offer a much more transportable, useful means of transferring geographic information compared to physical globes, and moreover, allow the user to cater to specific mapping tasks. One can choose from hundreds of projections to best serve the scale and function of the map, whether it is for a small-scale map of the entire world or a detailed area of a city. If one is looking to calculate the true distance between Washington, D.C. and Kabul, for instance, one should use an equidistant map. There is a map projection to serve almost any criteria. Ultimately, the user has the power to decide and can even use multiple ones to map the same area as I did below.

In this week’s lab we explored three classifications of map projections - equidistant, conformal, and equal area – based on distortion properties. The equidistant projections – Equidistant Conic and Sinusoidal – both maintain distances from the center or along specified lines. I mapped two conformal projections – Mercator and Stereographic – that preserve angular relationships and the shapes of local areas. Lastly, the two equal area projections – Mollweide and Bonne – maintain the same proportional areas as the real world and exhibit true directions from the map’s center. Exploring these various map projections and their characteristic distortions heightened my geographic understanding and helped me appreciate the importance of educated mapmaking and reading.

Lab 4 - ArcMAP

Navigating ArcMap was an overall positive experience, albeit requiring much patience and further practice. Since my first time going through the tutorial primarily consisted of just following step-by-step directions, it was not until the second and third time that I started to really think about and grasp the purpose and usefulness of the program. I learned that it is essential to have the goal of the map in mind from the beginning and throughout the mapmaking process. What do I want to map? What elements need to be included for readers to understand my map? Such are questions that I need to answer at the outset; they will help define how I navigate the ArcMap program.

The goal in this tutorial was to create a map for a county seeking to expand its airport. We considered noise affecting schools and houses near the airport, as well as increased traffic along major roads. With each exercise, I included new features, referenced, and worked with the data to create complementary, informative maps.

GIS possesses significant potential in geographic data exploration and map creation. It has real-world value, as it helps communicate and work out problems effectively with more visual impact. Spatial data is used to explain patterns and predict relationships between populations and other elements mapped. By enabling the user to selectively reference data, one can narrow down variables of interest for focused study. Furthermore, computer-based GIS allows for analysis of a large amount of data in a timely manner.

GIS is not without possible pitfalls. From my initial experience with ArcMap, I realized that extensive practice with the program is needed to fully utilize all the tools to create proper maps. The technical know-how involved limits GIS software to educated users. GIS may oversimplify the world as well, failing to take into account the full context of the variables. As user-centric representations of the world, GIS maps as with all maps may vary according to the creator’s intentions and capabilities. This can lead to ambiguity or misinterpretations.

I plan to continue exploring and using ArcMap consistently to become a truly equipped, knowledgeable mapmaker and critical reader. The following is the map that I produced through the ArcMap tutorial: