Geography 7 Lab 7

 
The legend of the map indicates that the darkest shade of green has the highest percentage of black population in the United States for about 53.197% to 86.4887%. The majority of the black population is located around the south-eastern coast. I think this result will not surprise most of the people have the basic history knowledge of the United States. The west coast contains a low percentage of black population which most of them, about 4% to 12% of the total black population, are situated in middle and south California. The distribution range of the map is from 0.01% to 86.4887%.

The Asian population in the United States is evenly distributed around the East coast (New York city and the nearby states) and the West coast (San Francisco, Los Angeles, and the state of Washington). It is easily to understand that the Asian has a traditional tide with those regions when they first migrated to the states but it quite surprised me when I discovered some of the concentrated population in southern Taxes. The range of the map is from 0.0085% to 46.0387%.

This map shows the distribution of some other race population by county. By this census, some other race population refers to population that are not identified as Asian, Black, and White.  Overall, most of the population of other race are found along the south-western coast, which is the border between the United States and Mexico. We can also find a dense some other race population in the state of Washington. The range of the map is from 0.00795% to 39.0795%.

Most of the result of census 2010 are not surprised me with a basic knowledge of U.S. history but this lab is really helpful to let me actually work with the real census data with the ArcGIS application. After completing those labs, I have gained rich knowledge of dealing with complicated geographical data by the application.

To conclude the course, my impression of GIS changed. Before taking this course, I thought GIS is all about playing and dealing with some maps but now I understand that the study of GIS is far more than this. The use of GIS in our daily life really helps people to organize and analyze spatial data. Also, the application ArcGIS is one of the most important elements in the field that let us deal with the complicated data directly with an user-friendly program. After completing such a number of labs, I realize how to use the application to due with different kinds of map projection methods, the analyze of population census, and etc.

Geography Lab 6

 

 

This lab was an easy one but I still discover a lot about the GIS software and the application of raster data model. Raster data is a combination of grid of cells or pixels with specific values. According to the lecture, raster data is excellent for present continuous phenomena, such as elevation & temperature, because the editor can simply mapping out the small cells and change them accurately. However, this simple data structured data model still has some disadvantages. Because of the revolution and geographical changing over time, we can always discover errors when we look close to the cells. Also, it is very different for spatial analysis because no one have that energy or passion to measure the changing phenomena all the time for an absolute accurate data. When we are using raster data model, we should remember there will always be obvious mathematically errors among the cells on a large scale map.

Geography 7 Lab 5

Distance between Washington D.C and Kabul:

Gall Stereographic: 7,216 miles

Mercator: 10,077 miles

 

Distance between Washington D.C and Kabul:  

Cylindrical Equal Area: 10,120 miles

Mollweide: 7,909 miles

Distance between Washington D.C and Kabul: 

Cylindrical Equidistant: 5,080 miles

Conic Equidistant: 6,989 miles

For this lab assignment, I created six map with different map projection types. The first type of map is conformal map projection which I chose gall stereographic and Mercator projections. They preserve angles locally. The Conformal map projection has meridians and parallels oriented at right angles to each other. The map projections preserve the correct angles between locations which are very useful for global navigation. Some downfalls for conformal map projections may be the wrong size of some regions, such as the south pole will occupy more than half of the map.

The second is equal area map projection which I chose cylindrical equal area and Mollweide projections. They preserve areas for the map. Some downfalls will be the distortion of the grid line, it will result in wrong, biases, or inaccurate information to the viewers.

The third type of map is equidistant map projection which I chose cylindrical equidistant and conic equidistant projections. They preserve the distance between points. Each of the map projections are unique that they are useful in their own ways. However, the area and angle information are not accurate in this projection so that it may be misleading sometimes.

As map projections become more famous around the studies of earth, cartographers should understand different advantages and shortages about each map projections. Each of them have their unique purpose that help human to express and explain the information of earth surface in detail.

Geography 7 Lab 4

The ArcGIS was quiet confusing first time because there are too many functions on the application. After I became more familiar with the tools, I think it is an amazing program that we can manage the map and data very detail but sometimes simple functions such as changing fonts, moving objects, and coloring the objects became very complicated for me. At this point when I finished the map and poster, I am still confusing with some points that were mentioned on the tutorial. I think it will be more comfortable for me to complete the tutorial several more times.

The purpose for the ArcGIS program is to answer complicated GIS questions. For this assignment, our question is about a proposed airport expansion. The question is easily answered by the applying of spatial data set to a visual model that is convenient to the users. The program consists of rich functions that we can easily find out the answers for the complicated questions.

I think this application has many potential. It able the users to explore much more beyond the simple map making process. In reality, it will be very difficult for a normal user to generate a complicated chart or graph but you can analyze both of them by using the program. The data can always clearly represented by the program. Also, the program allows the users to access to many function, such as drawing and editing. It becomes very convenient when there is such a long list of build-in tools in the program.

Next, there are still some pitfalls to the ArcGIS program. For such a complicated system, users need such a long time to experience and learn about it. Most of the time, users need to put more time in learning about the program rather than learning the knowledge of his/her own fields. Overall, I think the most important pitfalls for the program is that it is not user-friendly enough. For me, I need to review the tutorial every time in each step. Sometimes even with the tutorial, I am still confusing in some parts.