Lab 6

                Digital elevation models are digital representations of the Earth's surface. Digital elevation models can be represented through raster models or TIN (triangulated irregular network). The maps we created in this lab included shaded-relief, aspect, slope and 3-Dimensional maps.  DEM's are widely used for multiple map applications. Creating a DEM was extremely easy and I think that is an important aspect to DEM. The fact that digital elevation models are relatively easy to create is helpful when creating physical models of the Earth's terrain. Moreover, DEM's can exhibit morphology of land elevation and this is significant in terrain analysis. However, a DEM map is not 100% accurate as a cell value can hold only so much detail. Overall, this lab was an enjoyable experience.

         

lab 6

A map projection is defined as a 3-dimensional representation of the Earth on a 2-dimensional surface. In order to construct a map projection, developable surfaces are necessary. There are three types of developable surfaces that you can use; planes, cylinders, and cones. Selecting a certain type of developable surface, impacts the way the map image is distorted. Map projections are often classified by the map elements they preserve. The three types of map projections we created in this lab were the equidistant map projection which preserves distance, equal area map projections preserves area, and conformal map projection preserves projection.

            Map projections are important in providing accuracy of a map. In viewing the six different maps, I noticed the disparity of distances between the two cities of Washington D.C. and Kabul. It was interesting how each map, even the original map we created, showed different distances between the two cities. As a result, choosing the right map is significant when attempting to display desired features. Map projections are also significant because they allow people to see what is actually on a map. For example, the conformal map projection I used, the Hotline Oblique Mercator and Mercator, do not accurately reflect the sizes of each country. This is important information for people who are traveling.

            One of the perils of map projections is that it is almost impossible to preserve all properties of the Earth. Since the Earth is not physically smooth it cannot be perfectly projected onto a 2-Dimensional surface. In turn, the accuracy of one map element must be sacrificed in order to present an accuracy of a different map element. Although the equidistant map projections such as the Two-Point and Conic preserve area between designated points, they distort area size which impacts the representation of distance between areas. Additionally, equal area maps such as Behrmann and Craster Parabolic, accurately represents the area of each continent. However, discontinuities in the map skew the actual distance and distance cannot be measured accurately.

            There are a few overall potentials of map projections. The fact that we are able to easily access and obtain information through maps is an example of a potential of map projections. Another aspect to map projections is that it is user-centric and people have the ability to specialize their maps according to their preferences. Map projections are a very useful tool when trying to explore different aspects of society. Similar to any program, there are always potential drawbacks that should certainly be taken into account when creating or exploring maps.

lab 4

       My experience using the ArcGIS program was certainly a challenging one. I do not have very much computer experience so it was very difficult following the steps and making sure to complete each step correctly. I think that people with more computer experience can find the ArcMap program relatively easy to use.The tutorials were very helpful and if there were not any tutorials, I am sure I would have struggled even more. In the end, I appreciate how elegant the map turned out. It was certainly a challenging experience and hopefully with more practice, I can continue to enhance my computer/GIS skills.
    One of the benefits of this program is that you can easily see the details on a map.  It was fascinating to see all of the different information available by using the different features on ArcMap. Being able to view one specific detail and view all of the details in one view, is an effective way to collect information. Often times, the simplicity of maps can be overlooked. Using ArcMap showed me how important using charts and the attribute tables. Overall, a major benefit of this program is being able to complete multiple tasks on one program.
     Besides the potential benefits of GIS, there are also consequences. I think it is important to note that there is an immense amount of information that can be presented. This is difficult when trying to learn how to layer and present the data. It took awhile for me to get to used to the different toolbars, layout features, and other editing features. It was frustrating when I had to switch to zooming in and out, and trying to remember how to return to the original view because I was not comfortable with the system. Another pitfall, is that we constantly have to save our work because if we do not, we have to start all over again. Secondly, it is extremely time consuming to adapt the skills necessary to become comfortable using GIS. Additionally, since all of the data provided is established from the work of geographers, we have to rely on how accurate and how often their data is updated. In my opinion, the biggest downfall of the program is how challenging it is to use.
       In my opinion, the potential benefits of GIS outweigh the bad. This system allows people to discover relationships which in turn can be easily transmitted to the public. Although GIS is difficult to use and is sometimes hard to understand, it can be very effective in helping people understand the various aspects of society. Overall, this program allows for maps to be constructed and manipulated to present multiple dimensions of geographic data in an effective way. As this program becomes easier to use, we can further advance the way in which we present geographic information.