Many techniques have been developed by humans for navigation purposes. These techniques vary in complexity, ranging from requiring simple tools to advanced technology. For example, humans have used the stars, moon, and sun to navigate for hundreds of years. Now, most individuals rely on GPS technology to navigate to their point of interest, however in our previous lab, we discussed the unreliability of technology. Due to this, this weeks lab is designed to teach us how to navigate using a pace count, which does not require the use of advanced technology. During this activity we constructed two navigation maps that will be used during our next weeks exercise at The Priory, in Eau Claire, Wisconsin.
Methods
This week's lab consisted of two activities. For the first activity, our class went outside to determine our personal pace count for a 100 meter distance. I determined I walked 68 steps within the 100 meter distance. This information will be used in our next week's lab when we begin navigating at the Priory.
For the second activity, we were instructed to make two navigation; one with a 50 meter UTM grid, and another with geographic coordinates in decimal degrees. Aside from these requirements, we were encouraged to design the maps how we personally deemed best fit for pace count navigation purposes.
To design these maps, I began by making the UTM grid map. I beganby adding the background aerial imagery of the city of Eau Claire created by my professor Dr. Joseph Hupy. I then located the Priory in the image and fit this to the data frame. From here, I changed the coordinate system to NAD_1983_UTM_Zone_15N and then navigated to the properties of the data frame to add a UTM Grid measured at 50 meters. A grid is added to the data frame by entering the data frame properties window, followed by selecting the Grid tab (Figure 1). From here, I select New Grid. A Grid Wizard window appears, and walks you through the parameters of setting up the grid. I selected the Measured Grid grid type, which will divide your map into a grid of map units. Most default parameters were selected within this Wizard window, however I changed the Interval setting to 50 for both the X and Y axis. Because this map was given a UTM projection, the map units are in meters. Therefore, setting an interval of 50 created a grid with grid squares measure 50 meters for both their X and Y lengths.
I repeated this process to create the Geographic Coordinate System map, however I made a few adjustments. This time I added the same aerial imagery of the Priority however set the coordinate system to GCS_WGS_1984. From here, I entered the data frame properties and made another measured grid for this map. Because, this map is in an unprotected coordinate system, the grid is measured in decimal degree intervals of about 0.0006.
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| Figure 1: Displays the Grid tab of the Data Frame Properties window. The highlighted option button, "New Grid", is where to begin creating a grid for the data frame. |
Along with the grid, I added contour lines to the map and labeled their elevation on both maps. Additionally, I included the final map requirements of a scale bar (in meters), a representative fraction ratio (in meters), compass, legend, title, and data source. The final products of these maps can be viewed in figures 2 and 3.
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| Figure 2: Aerial image of the Priory with a UTM 50 Meter grid overlaid. |
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| Figure 3: Aerial image of the Priory with a geographic coordinate system grid measured in decimals degrees overlaid. |
Discussion
While designing my maps, it was important to keep in mind what my maps will ultimately be used for. For our next week's navigation project, we will be divided into groups of three and given a designated path that is maps out by various navigation points. One team member will stand at a marked point, and another will start at this location and will keep their pace count until they reach the next marked point. Because this will be the first time myself and my teammates have walked this path, it is important to design a map that will inform us of the terrain is like within our path ahead. However, we discussed in class that often times it is a common misconception to add a lot of data to maps used for large scale field work. After learning this, I decided to keep my maps simple yet informative by adding only grid measurement and contour lines with elevation data. I added the contour lines in hopes that it will help inform the map reader of what the terrain elevation is like in places they are unable to physically see.
Furthermore, it is evident that the difference in coordinate system would effect one's ability to navigate. Knowing be measured our pace out in paces/meters, it seems to me it would be very difficult to convert this into paces/decimal degree. My assumption is that the UTM coordinate system is the best option to use for our navigating map due to this fact it has a map unit of meters. During next week's activity, we will be combining the use of these grid navigation maps with the pace count and compass navigation technique. In my field activity #6 report I will document the methods and analysis how well our methods worked while navigating at the Priory. Additionally I will review which features are more helpful to include in the navigation map.
Conclusion
This weeks activity was designed to introduce our class to the navigation techniques that requires the use of grid maps and pace counts. This lab is a two week activity, that began this week with the creation of our grid maps. In order to create functional maps, I was required to understand how UTM and geographic coordinate system grids are used for navigating. This gave me practice in designing a map for a specific field methods use.
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