Field Activity 7: Development of a Navigation Map

Introduction

Stored within the hippocampus of the human brain there is an inherent sense of direction that enables the process of navigation to happen. A study done at University College in London indicated that those who perform navigational tasks regularly have more developed hippocampi compared to those who do not(Maxwell, 2013). In order for one to utilize this inherent sense of direction to successfully navigate, a few additional tools are necessary.  First, a location system is needed to identify location in reference to surrounding area. Often location systems employ a projected coordinate system to accomplish this. These coordinate systems entail a number of systems more precise than latitude and longitude in order to facilitate navigation on a large geographic scale. The second component for successful navigation is an actual navigational tool such as GPS technology or a map. In this lab, two large scale maps of UWEC`s Priory on Eau Claire`s southwest side (figure 1) will be created for future use in navigation of the area. One of the maps will use the Universal Transverse Mercator (UTM) coordinate system to give spatial information in meters and the other will use the Geographic Coordinate System to display the same spatial information as decimal degrees. The UTM coordinate system is divided into 60 zones, each being six longitudinal degrees wide(esri). Each zone is then split at the equator to form north and south sections of each zone (figure 2), the navigation area falls into zone 15N. The UTM coordinate system is ideal for land navigation using large-scale maps because it is measured in meters and can be tied to a distance measuring system. The Transverse Mercator projection used by this coordinate system is a cylindrical projection that does not maintain direction on small scale maps, however it is appropriate for the navigation area because it is a large scale map and falls within one single UTM zone. The geographic coordinate system references latitude and longitude to identify location in terms of decimal degrees. This is helpful information to have when using a GPS, as the technology uses this system to identify location.

Figure 1. Location of navigation activity from Google maps

Figure 2. UTM zones of contiguous United States nps.gov

Methods

                The area to be mapped was UWEC`s Priory and a geodatabase with the navigational boundary, remotely sensed imagery, and a contours map was provided. Begin with a blank ArcMap document, it is then best to copy and paste the geodatabase into a private folder connection where it can be altered. The first item added to the map was the navigation boundary and the source information inspected. The layer had a UTM projected coordinate system, making the UTM the first map created. While creating these maps, it is important to bear in mind that they will be printed and used for navigation.

Before doing anything else, change the layout to an 11X17-landscape format. The next step is to create contour lines of the area; the land surrounding the Priory contains a lot of relief and contour lines will assist in spatial navigation of the area. To do this, the existing 2-foot contour lines layer was added to the map for examination. Contour lines every two feet seemed a little excessive and a new two-meter contours layer created from one of the elevation model layers using the contours tool. After this was accomplished, each provided raster image of the navigation area was placed on the map to determine the best backdrop. One of the true color raster images seemed to be the best fit and set to a 40% transparency allowing the contour lines to be more visible. The selected image then needed to be projected into the Transverse Mercator projection with the appropriate UTM coordinate system. With the navigation boundary, contour lines, and raster image background in place, it was time to switch to layout view and add all the necessary elements. One of the more tricky requirements for this map was the grid with appropriate labeling. It is necessary to be in layout view to accomplish this task and can be found in data frame properties, under the grid tab. For the UTM map, make sure all layers included in the map are in the appropriate Transverse Mercator projection and the grid should be at 50-meter intervals on the X and Y-axes. The remaining elements include a north arrow, scale, information about projection and coordinate system, source information, and your name so no one else can take credit for all your hard work. The map with geographic coordinates in decimal degrees requires all the same elements however; the appropriate project tools must be used to change all layers to a geographic coordinate system. After this has been accomplished and all the UTM layers removed, a grid with decimal degree divisions can be placed over the map.  

Results/Discussion

                 Both maps were created with the goal of being user friendly and usable for those without field navigation experience. The two resulting maps both include two-meter contours in hopes that relief can be used as a guide for spatial orientation in the field. They also include aerial imagery backgrounds to assist in spatial orientation once on location. The UTM grid has finer spacing to facilitate the tracking of distance navigated (figure 3). The GCS grid does not include spacing quite as fine as the UTM, but if given a current location in decimal degrees, one should be able to use the map to determine a relatively accurate location within the navigation area (figure 4).

Figure 3. Map with UTM grid

Figure 4. Map with GCS grid

Conclusion

                The ability to perform a simple spatial navigation activity using a map is an important skill to have. Not only have studies shown that it promotes activity in the hippocampus, but they have also shown that this method of navigation may be better for the brain that reliance on a GPS for navigation (Maxwell, 2013). Furthermore, technology may fail and one may need to utilize their inherent sense of direction to navigate out of a remote area or to make it to a job interview using landmarks and directions. This lab challenges one to consider what map characteristics would be useful for navigation and is an excellent precursor to an actual navigation activity.