Week 6 - Lab 6

Week 5 - Lab 5

1. There are 99 counties in the state of Iowa.

2. Fulton County was the county in Georgia with the largest population in 2001.

3. There are 39 cities in Washington with a population greater than 15,000.

4. The aggregate length of interstates that are crossed by the outline of Los Angeles County is 3,851.14 miles.

5. 1,367,445.89 acres of urban area lie within Los Angeles County.



6. 522 zip codes have their centroid in LA County.

7.

8. The Native American Indian Reservations that lie within 75 miles of Thurso are the Doncaster Indian Reserve 17, Kitigan Zibi Indian Reserve, Kahnawake Indian Reserve 14, Kanesatake Indian Reserve 16, and Akwesasne Indian Reserve 15.

Week 4 - Lab 4

The following three maps depict the percentage of specific racial groups by county. Demographic data is provided by the US Census 2000.

The black alone population clustered in the South-East of the contiguous United States and also along the Southern half of the Atlantic Seaboard in 2000. States that contain counties with the highest percentage of black alone populations are Louisiana, Alabama, Missouri, Arkansas, Georgia, South Carolina, and North Carolina. Some counties have percentages of Black Alone populations as high as 86.49%. Such clustering lends itself to the process of social construction and must be viewed in the context of history. With the transatlantic slave trade, spanning the 16th to 19th centuries, the use of European indentured servants was replaced with the importation of African slaves. Labor, as provided by African slaves, became an integral component of the triangular trade that involved raw materials from the New World as well as manufactured goods from Europe. In tandem with natural endowments that provided climatic conditions amicable to plantation-styled operations, the social construct and inhumane practice of slavery was established in the South. Furthermore, with the passage of the Northwest Ordinance in 1787, slavery was prohibited in areas North-West of the Ohio River. Slavery, and consequently the African-American population, became an attribute constrained to a geographic area. However, with the end of the Civil War as well as the 13th Amendment, slavery was abolished as a social construct in the United States. Nevertheless, despite the abolishment of slavery and the Great Migration of the early 20th Century (which explains small concentrated clusters of African-American communities in the North), the Black Alone population has largely remained in the South. This testifies to the long-standing roots of history and perhaps serves as an allusion to the remaining socio-economic inequalities still remaining.

The Asian Alone population percentage map depicts general clustering along the West and East coasts of the United States. States with such clustering are California, Oregon, Washington, Virginia, New Jersey, and Maryland. It is important to note the range of percentages involved in this map. Unlike the Black Alone population percentages, the percentile ranges for the Asian Alone percentage extend to a maximum of 46.04%. Furthermore, the overwhelming majority of counties are categorized with the lowest range of Asian Alone percentages - 0.01%-1.68%. Such a racial distribution can likewise be attributed to history and specific immigration policies that were enacted. Asians, as a race, are a relatively newer immigrant minority to the United States. Large scale Asian immigration began in the mid-19th century with an influx of Chinese and Japanese immigrants meeting labor demands for the expansive railroad projects to conquer the Western expanse of the US. However, with 'Yellow Fever' rampant and racial angst against Asian immigrant laborers, policies such as the Chinese Exclusion Act were enacted to restrict further immigration. Even well into the 20th Century, the McCarran-Walter Act of 1952 maintained a quota system, effectively banning large scale Asian immigration. However, with the passage of the historic 1965 Immigration Act, the quota system was reformed and Asian immigrants began to flow in in larger volumes.

Members of the Other Race Alone population cluster in the South-West of the United States. Again, noting the population percentile range, the Other Race Alone population percentage spans a smaller level of concentration. Furthermore, the mean and median population percentages differ less, as suggested by the smaller ranges, which means a less diffusive spread. The states that contain the bulk of the clusters are Texas, New Mexico, Arizona, California, and Washington. To properly analyze this map requires an explanation of the demographic data, as provided by the US Census 2000. The Office of Management and Budget (OMB) revised the definitions of race and ethnicity, which the Census uniformly used in 2000. For the US Census 2000, four racial categories were established - Black, Asian or Pacific Islander, White, and American Indian or Alaskan Native. Furthermore, "in general, the Census Bureau defines ethnicity or origin as the heritage, nationality group, lineage, or country of birth of the person or the person's parents or ancestors before their arrival in the United States. People who identify their origin as Spanish, Hispanic, or Latino may be of any race" (US Census Bureau). With these definitions of race and ethnicity in play and no racial category for people of Hispanic ethnicity to choose, my assumption of who composes Other Race Alone largely consists of people of Spanish, Hispanic, or Latino origin.

This Census Map series depicts racial concentrations of the country's demography. Using data from the US Census 2000, the maps break down the US, county by county, and show the population percentages of Black Alone, Asian Alone, and Other Race Alone populations. In all three maps, a relatively discrete cluster of the respective races are shown. Each population is diffuse over the entire nation, as in almost every county holds a member of each racial grouping, yet there are distinct areas of racial groups. For the Black Alone population, the cluster is mainly in the South-East, the Asian Alone population clusters largely on the Pacific and Atlantic coasts, while the Other Race Alone population is found mostly in the South-West of the United States. Such clustering can be attributed to the historical processes involved in determining social constructs, as well as immigration patterns. Certain laws and policies shape the movements of people. Furthermore, the map series provides a sort of sociological insight into the mentality of people. In general, people like to be around similar people. In terms of social and cultural acclimation for immigrants, residing and working within a more familiar environment helps. Lastly, the map series attests to the long-lasting molds created by history.

GIS as an analytical tool is quite powerful. I was very surprised at the ease with which Census data could be inputted as an attribute table in ArcMap through Excel. By combining geographic spatial data with demographic statistics, an entirely new data base was created. The visuals make stunning remarks and allow for generating interesting conclusions. Because GIS can combine data from different sources and provide locational background, it is extremely helpful in analysis. Furthermore, multiple data sets can be easily interchanged. For example, the Black Alone, Asian Alone, and Other Race Alone population sets were fluidly moved on and off the map. Nevertheless, it was shown once again that conclusions are only as good as the data inputted. The maps that are generated rely on the quality of the Census data as well as the way in which demographic statistics was organized by the US Census Bureau. Overall, GIS serves as a powerful analytical tool and can be used well in combination with other sources of data.

Week 3 - Lab 3A

The process of map projection essentially involves the conversion of an image from a three-dimensional surface unto one that is two-dimensional. Such a process inherently involves distortions along the way. Depending on which properties a cartographer wants to preserve, different methods of map projection will be used. Map projections can generally be classified by two main qualities: (1) by developable surface and (2) by preserved properties. The most common types of developable surfaces historically used by cartographers are the plane, the cone, and the sphere. With the advent of computers and geospatial technology, unorthodox planar surfaces are now used in map projections. The above three sets of maps depict three common methods of projection, as characterized by preserved properties - Conformal, Equal Area, and Equidistant, respectively.

The Conformal projection preserves angles locally. Its visually highlighting characteristic is the intersection of parallels and meridians at right angles. The benefit to such a projection is that local shapes are correctly preserved without much distortion. Looking at the Mercator projection, the latitudinal and longitudinal demarcations intersect uniformly in 90 degree angles. But as portions of the map move away from the equator, the images are increasingly distorted. Antarctica looks as though it covers nearly a third of Earth's surface. The distortions are clearly seen by observing the 30x30 World Graticule, as the grids become more elongated as they approach larger latitudes. The Gall Stereographic projection was developed as a way to improve the distortions found with the Mercator projection. And it does so by using the same cylindrical projection method but has the plane intersect at 45 degrees North and South to reduce stretching. The differences in methods produce rationally different results when measuring the distance between Washington DC and Kabul. The Mercator projection indicated a distance of 10,135.44 miles, while the Gall Stereographic projection showed the distance to be 7,141.04 miles. The actual distance between the two capital cities is 6,923.39 miles. The Gall Stereographic projection does a better job at estimating the distance because it somewhat adjusts for distortion and because both DC and Kabul reside within the 45 degrees North-South region, where distortion for the Gall projection is the lowest.

Equal-Area projections attempt to maintain proportionality between areas on a map. Unlike conformal projection, the latitudinal and longitudinal angles are not always perpendicular. However, the relative sizes of countries are presented in a much more accurate manner. Equal-Area projections do not attempt to render perfect size proportionality across the entire globe, but rather focuses on specific areas. The Sinusoidal projection is centered along the Prime Meridian. Thus, all parallels that intersect this central meridian do so in perpendicular fashion. Portions of the map that extend further away from the Prime Meridian experience greater distortion. This serves as an explanation for the over-exaggerated distance (8,117.75 miles) between DC and Kabul as purported by the Sinusoidal projection. The Bonne projection is also an Equal-Area projection that centers itself along the Prime Meridian. Distortions are slightly better accounted for as one moves away from the center. Thus, the distance between DC and Kabul, according to the Bonne projection is 6,732.80 miles. Due to the method of projection and intended preservation of area, Equal-Area projections are typically more useful for mapping out smaller areas, such as continents or countries, rather than the entire globe.

Equidistant projections preserve the distance between the center of projection to any other area on the map. And therefore these projections were the closest towards asserting the distance between DC and Kabul. In the Equidistant Conic projection, all latitudes run parallel to each other at a uniform distance. As the name suggests, the projection involves mapping out the globe unto a cone. Out of the six map projections, this one was the most accurate in determining the distance between DC and Kabul. It was roughly 50 miles short, at 6,971.74 miles, in its calculation. The Equidistant cylindrical projection is similar to the Equidistant Conic projection, but uses a cylinder as its two-dimensional plane. Each grid in the 30x30 graticule is the same size. Both Equidistant projections employ standard parallels - the latitude at which the two-dimensional plane tangentionally (or secantly) intersects the three-dimensional globe. That intersection then becomes the reference point from which equal distance is given.

Projections are an essential part of mapping. The type of projection used will determine the distortion of the map as well as the preserved qualities of the map. As each map is used for different purposes, the type of projection will be decided upon that underlying basis.

Week 2 - Lab 2B

In my first experience with ArcGIS, I can conclude that the program is not first-time user friendly. Going through the tutorial, I often felt lost and unsure of what I was doing. Furthermore, relatively basic tasks such as classifying different regions by color seemed complicated. But as with most new things, technical skills develop over time. However, such a tool that is able to compute complex data can be powerfully used for many purposes.

Insofar as GIS is an information system helpful in organizing spatial data, ArcGIS provides the proper tools for insightful analysis. By breaking down spatial components into layers, the program offers combinatorial set ups that break down an area into its constituent parts. In the above example, the map contained different layers for the county, schools, the runway tarmac, as well as an area that averaged 65 decibels due to noise generated by the airport. By organizing maps in this manner, ArcGIS can isolate specific variables to determine relations between different parts of an area. For example, the software was able to isolate the districts within the county that were affected by noise from the airport. And that information was then able to be organized to give a spatial representation of how many people were affected by cross-referencing it to population density.

The main drawback I sensed from using the program was that the accuracy of the maps is entirely reliant on the geodatabase. If the information that is provided is wrong, then the entire produced map will be incorrect as well. In the tutorial, the data was provided. It was accurate and comprehensive. But if GIS was to be used in more unfamiliar or less-detailed areas, the accuracy can be severely compromised and it will have failed in organizing spatial data correctly. Nevertheless, with the availability of advanced technology, such as satellites that provide accurate imaging, data is readily available. As the adage goes: "garbage in, garbage out".

The aspect of ArcGIS that most impressed me was the ability to use sources outside of typical cartographic maps. In one portion of the tutorial where Census tract information was utilized, the software was able to create a layer that showed population density broken down by district. In being able to bring in various types of data, GIS becomes a versatile tool. Because all things occur within the realm of space, GIS can be adapted to any industry or field of study. For example, it is applicable to public health in that it can track the spread of disease and possibly locate the origin by mapping the outbreaks. And for civil engineering, GIS can be used to find the most favorable locations for building bridges and roads. In the tutorial, I was asked to build a new road on the map that connects an old road leading into the airport back onto an already established arterial. Custom features for building cities and developing areas makes it a powerful tool for urban planning as well.