INTRODUCTION
Navigating over land using only a map and compass can be a useful skill when these are the only tools available. Many times there are better and more advanced methods of navigation because of high tech geospatial devices. However, these high tech navigation devices can cost a lot of money, and such a high level of navigation is sometimes not necessary for simple excursions. High tech navigation equipment can also be quite cumbersome and bulky which can slow someone down if they're navigating across rough/difficult terrain. Compass and map navigation; therefore, is often times the cheapest, easiest and quickest option where land navigation is concerned. There is actually a sport called orienteering that involves competitors using only a map and compass to navigate from point to point as a type of race.
The tasks to be performed before actual navigation can occur in field exercise three are two fold. First, the navigator must measure his/her pace count. A pace count is taken so that the navigator can accurately pace off distances on their map that corresponds to the area they are navigating. Second, the navigator must create an appropriate map of the area to be navigated. In my case two maps will be created that correspond with my area of interest (the UW-Eau Claire priory). The first map created will be a Universal Transverse Mercator (UTM) coordinate system with a 50X50 meter grid attached for the purpose of easily measuring off my pace counts. The second map will be created using a Geographic Coordinate System (GCS) that shows the actual latitude and longitude associated with my area of interest. The second map will contain a grid as well, but one that is measured out in decimal degrees.
METHODOLOGY
Pace Count
The first task I had to complete before navigation could occur was measuring my pace count. A pace count is usually measured at 100 meters. Basically a person counts how many paces they take within that 100 meters to figure out their 100 meter pace count. A pace equals two steps or every time the right foot takes a step. An average pace count for a person of average height (5'5"-6'0") would be between 60 and 70 paces per 100 meters. For example, I'm 5'10" and I have a pace count of 65. Now that I know that I take 65 paces in 100 meters I can create a grid map that allows me to accurately pace off distances in meters. Below in figure 1 is an example of my pace count break down
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| Figure 1: My pace count breakdown at distances of 100, 50, and 25 meters. |
Map Creation
The second task I had to complete before navigation could occur was creating the two maps of my area of interest (the UW-Eau Claire priory). This task was completed using the program ArcMap 10.2.2.
The Geodatabase
The Geodatabase
First I had to import the priory data provided by the instructor. The entirety of this data was held inside the priory geodatabase. A geodatabase is a repository for files that contain the same spatial data and can perform interoperable tasks. Interoperability is the ability of feature classes to work/communicate with one another and is one of the main strengths of a geodatabase. The old system of geospatial technology relied on shapefiles that contained separate spatial data and could not perform interoperable tasks.
Adding Feature Classes
Adding Feature Classes
Because of interoperability I was easily able to add and omit feature classes that would aid my map or harm it. I added the five meter contour lines feature class, the navigation boundary feature class, and an aerial image of the priory to create my two maps. I omitted every other feature class because they added many unnecessary details my maps would not need. In figure two below, all features within the priory geodatabase are shown. Figure three below shows the maps as they appear after the three feature classes have been added.
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Figure 2: Shows all the feature classes within the priory geodatabase. The priory geodatabase is circled in green, and the feature classes within the geodatabase that I added to the maps are circled in red. 
Figure 3: shows the two maps of the UW-Eau Claire priory. The 5 meter contour line feature class is depicted using dark red and lime green lines, the navigation boundary feature class is depicted using a faded grey outline, and the aerial image of the priory can be seen as the base for the whole map.
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Projecting the Data
After the desired feature classes were added to the maps I projected them using different coordinate systems. The first map was projected using the North American Datum (NAD) 1983 UTM coordinate system (15 zone). The UTM coordinate system uses a 2-dimensional Cartesian coordinate system to give locations on the surface of the Earth. The UTM system basically breaks the earth up into 60 vertical zones to keep distortion at a minimum. I specifically used the UTM 15 zone because Eau Claire is located within this zone; therefor, it most accurately displays the geospatial data. Figure four below shows a visual representation of the UTM coordinate system as it pertains to the United States and Eau Claire's placement in it.
Creating the Grid and Map Elements
Once the maps were properly projected into the UTM 15 zone I sized them using an 11X17 inch layout. After sizing the maps I then overlaid a 50X50 meter grid system onto the UTM map so my pace could accurately be measured on the maps. To create the grid I navigated into the properties tab which is located in the map's layers scroll down menu. Once inside the properties menu their is a grid tab that will open up the grid menu. Since I knew that I wanted a 50X50 meter grid to be overlaid on my map I used a measured grid with intervals set at 50 meters on both the x and y-axis. There are many other grid options including the amount of labeling and color schemes of the grid. My grid was a standard black grid with five tick marks in between the 50 meter vertical and horizontal grid lines to demarcate ten meter segments. The second grid was created by setting the x-axis interval at .000563 decimal degrees and the y-axis at .000350 decimal degrees. this created a grid that was similar to the 50X50 meter grid. The only other difference besides the x and y-intervals for my second grid was the stroke size of the grid line. I reduced it so the map below the grid would stand out more.
Once the grids were overlaid onto my map I added the necessary elements to make proper maps. These elements included a north arrow, a scale bar, a projection and coordinate system label, a data source descriptor, and of course my name. Once these elements were added I had two finished maps of the UW-Eau Claire priory. Figure five below shows the two finished maps.
After the desired feature classes were added to the maps I projected them using different coordinate systems. The first map was projected using the North American Datum (NAD) 1983 UTM coordinate system (15 zone). The UTM coordinate system uses a 2-dimensional Cartesian coordinate system to give locations on the surface of the Earth. The UTM system basically breaks the earth up into 60 vertical zones to keep distortion at a minimum. I specifically used the UTM 15 zone because Eau Claire is located within this zone; therefor, it most accurately displays the geospatial data. Figure four below shows a visual representation of the UTM coordinate system as it pertains to the United States and Eau Claire's placement in it.
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| Figure 4: shows the UTM zones of the United States. Eau Claire is located in zone 15. |
The second map was projected using the GCS World Geodetic Survey (WGS) 1984 coordinate system. The WGS system uses a standard spheroidal reference surface to define Locations on the earth. This system is not broken down into zones like the UTM system; instead, it is one gigantic system that encompasses the whole earth. This kind of system is more of a broad strokes approach to defining geographic coordinates because there is a mild amount of distortion due to it's all encompassing properties. The UTM systems ability to focus on smaller zones is what make it more accurate than the CGS system.
Creating the Grid and Map Elements
Once the maps were properly projected into the UTM 15 zone I sized them using an 11X17 inch layout. After sizing the maps I then overlaid a 50X50 meter grid system onto the UTM map so my pace could accurately be measured on the maps. To create the grid I navigated into the properties tab which is located in the map's layers scroll down menu. Once inside the properties menu their is a grid tab that will open up the grid menu. Since I knew that I wanted a 50X50 meter grid to be overlaid on my map I used a measured grid with intervals set at 50 meters on both the x and y-axis. There are many other grid options including the amount of labeling and color schemes of the grid. My grid was a standard black grid with five tick marks in between the 50 meter vertical and horizontal grid lines to demarcate ten meter segments. The second grid was created by setting the x-axis interval at .000563 decimal degrees and the y-axis at .000350 decimal degrees. this created a grid that was similar to the 50X50 meter grid. The only other difference besides the x and y-intervals for my second grid was the stroke size of the grid line. I reduced it so the map below the grid would stand out more.
Once the grids were overlaid onto my map I added the necessary elements to make proper maps. These elements included a north arrow, a scale bar, a projection and coordinate system label, a data source descriptor, and of course my name. Once these elements were added I had two finished maps of the UW-Eau Claire priory. Figure five below shows the two finished maps.
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DISCUSSION
I ended up only adding three feature classes to my maps: the five meter contour lines feature class, the navigation boundary feature class, and an aerial image of the priory. I did this to create a map that was not too busy on the eyes. This basically meant that I wanted to be able to look at a map that was as simple and bear bones as possible. The fiver meter contour feature class will allow me to observe the changes in elevation and the overall relief of the land surrounding the priory. These contour lines are depicted using easily seen dark red and bright lime green lines. The navigation boundary feature class was not entirely necessary for me to add, but it demarcates my exact area of interest with a subtle dark grey box. Although I could have omitted the aerial image of the priory, I decided to add it to my maps so I could observe features such as trees, roads, and buildings as well as the relief surrounding these features.
Because the UTM coordinate system is able to focus on specific zones, the UTM map (red contours) had less distortion than the GCS map (green contours). This resulted in better resolution for the UTM map. This being said, both maps are very similar to one another with the key difference being the color scheme of the contours and different grid systems.
CONCLUSION
Creating these two maps of my area of interest is a huge boon to both my map making and navigation skills. Understanding the background and mechanics of what goes into a map is the best way to become a full fledged spatial thinker. Navigating the UW-Eau Claire priory using the maps I have created is going to be much easier since I'm the one with all the background knowledge.
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