This activity is to set up another activity that we will be performing later in the semester. We will eventually be navigating at the Priory, but first we must make two navigation maps that will assist us. One map is using Universal Transverse Mercator (UTM) and the other is using World Geodetic System (WGS). When using UTM, we will be navigating by using meters and when using WGS, we will use decimal degrees. We are split into groups of three and by using these maps, we must navigate to different locations within the Priory.
Study Area:
What is the Priory you may ask? Well to keep it short, it is a 110 acre piece of property that the University Foundation bought. It used to be the old St Bedes Monastery and now it is overflow dorm for college students and for the most part, a waste of space. The property to my knowledge is not used for much other than geography labs and "hiking" (if you can call it that). Regardless, it is located 3 minutes south of Campus on Priory Road, just south of highway 94 (Figure 1).
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| Figure 1: Location of the Priory relative to our university campus |
The first thing we did for this lab was to calculate our pace count. A pace count is basically a backwoods way of measuring distance when measuring tape is not available or practical. Most pace counts measure out to 100 meters and that is what we did as well. My pace count ended up being 61 steps per 100 meters, considering that for every time that my right foot touched the ground it was counted as a step. Pace count is something we had to keep in consideration while creating our maps.
To create our navigation map we used ESRI ArcMap 10.3.1 and used a Priory Geodatabase that already had layers for us to use. The creation of the maps and its features was quite easy, the only part that took some tinkering was the labeled grid that we all had to use. I created my own grid from scratch so I could make it as I saw fit for the upcoming lab. As said above, we had to create two maps in two different projections, one was in UTM and the other was in WGS. I gave both projections the relatively same grid system. UTM had spacing of major grid lines of 50 meters while WGS had the equivalent at 500 decimal degrees. On each map I made some of the coordinates a lot smaller if they were the same for the whole grid, such as 44 and 91 degrees for the WGS map. This allowed the smaller more detailed coordinates to stand out so they were easier to read once we were in the field. On each map I also added three sets of scales. The first scale was just a basic bar scale that represented how far 100 meters was (the length of our pace count), the second was a representative fraction (such as 1:3,100), and the third was map scale (1 centimeter on the map equals 31 meters in real life). These scales will help us when we are plotting our points as well as when we are in the field and are wondering how away we are from our destination. My maps also had a outline of the Priory Property to ensure that we knew where the absolute boundary of our activity went. Of course each map was fitted with a North Arrow as well as a set of Coordinate and Projection data. The final touch on the map was a layer of 5 foot contours which will help us have some idea of the lay of the land when we get out there.
A little more on the UTM coordinate system; It is a coordinate system set in the North American Datum (NAD) and is broken up into different zones based on varied longitudes. The zone that I used was zone 15N. 15 is the number of the zone from the starting point on the International Date Line and the "N" obviously stands for North because we are in the Northern Hemisphere. Figure 2 below illustrates the many zones that UTM has within America, each one being 6 degrees across. One of the advantages of UTM is that it is in meters and it has an absolute origin point. Within UTM there is some called the False Easting and False Northing and each zone has its point of origin starting on the intersection of the equator and the central meridian of the zone. However to eliminate negative numbers, the origin is set of to the east 500,000 meters.
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| Figure 2: A map showing the 10 different UTM zones within the contiguous United States |
Discussion/Results:
The final result was a map that was fit for any navigator. One of the hardest parts of this activity was finding the middle between too much and not enough. You want to put everything necessary on your map but not so much that it clusters your map and makes it hard to read when your out in the field. I always try and make my aerial rather large so we can see it better but I also left enough space around the margins so I could put supporting data such as the grid and scales. These maps were to be printed out in 11x17 sheets of paper for the upcoming navigation lab and our groups had to pick one of our maps to be used by the entire group. I was fortunate enough to have my group select both my UTM (Figure 3) and WGS (Figure 4) map to represent our entire group when we were out in the field.
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| Figure 3: UTM Navigation Map to be used during our navigation exercise |
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| Figure 4: WGS Navigation Map to be used during our navigation exercise |
Conclusion:
After creating this maps, there is NO doubt in my mind that the UTM coordinate system is more reliable and more practical for this activity. Decimal Degrees are great because they can get very accurate since you can just keep adding significant digits, but when your out in the field, being able to look at your map and quickly discern how far you are away from your target objective is the real deal. For this reason, I would hope that my group is able to use my UTM map due to its practicality and efficiency. I will note that both of my maps shown above DO have grid lines in place, but they just do not show up the best when exported in JPEG format. For this reason, our Professor is printing the maps out for us after we send him the maps in PDF format. Happy Navigating!
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