For this exercise we were to create two maps that are to be used in a later exercise. The maps are of a property outside of town that is owned by the University of Wisconsin-Eau Claire called The Priory. The priory was a former nunnery that was bought by the University in 2011 and started using the property for a child day care and a field methods laboratory in 2012-2013. We were to create these maps with one being in a coordinate system of decimal degrees and the other in Universal Transverse Mercator (UTM).
Each map will need to have specific coordinate system and projection requirements that are the most useful for their features and usefulness. I will go through each step of making these maps as well as the reasoning behind choosing each specific projection and coordinate system. I will also include some background information behind navigation, projections, coordinate systems and other things that I chose to include in my maps.
Methods
The first objective was to measure our personal pace count which is the length of two strides. To figure this out we needed to first measure 100 meters out. One person walked down the sidewalk behind Phillips Science Hall and another on the other end. The person at the far end held a receiver while the other held a laser measuring device. Once the person with the receiver was far enough away the person with the laser called out when they were 100 meters away. They then marked the point where that was and each of us took turns counting how many paces it took to traverse that distance. We counted every time our right foot was forward (two strides) and repeated this on the way back. On the way there I had 69 paces and on the way back I had 65. I took the average and set my pace count at 67. This will be used to measure out distances once we are out in the field at The Priory.
The next step was to create the maps I will be using out at The Priory. For the exercise we were given a geodatabase with all kinds of feature classes and data from The Priory. We were to chose from the data given to us what we needed to be most useful to us. I elected to use a satellite imagery of the area of Eau Claire County that The Priory was in, a five meter contour feature class of The Priory, and a feature class of the study area. I thought these were all that were needed when navigating The Priory in the future exercise. We then were to create a sheet with two separate maps on each side. One was to be in a geographic coordinate system and the other in a Universal Transverse Mercator (UTM) projection. The coordinate system map needed decimal degree measurements along the borders of the map while the UTM map need to have meter measurements. Each map will have their own usefulness when navigating.
In order to chose the correct projections for each map we need to know more about UTM and coordinate systems. Below is a image of the 60 evenly sliced UTM Zones across the globe (fig. 1). The equator separates the north and south UTM Zones. These zones help us create projections that give us an undistorted projection of specific zones on the globe. If you were to map in UTM Zone 34S for example you would get a great map of the area that lies in UTM Zone 34S but the rest of the globe would be distorted. So for my UTM map I chose a projection that encompses Eau Claire County, UTM Zone 15N. UTM projected coordinate system's are measured in meters instead of degrees so this map gives us a good representation of The Priory. Both maps were in the North American Datum of 1983 (NAD 83).
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| The 60 Universal Transverse Mercator Zones divided by the equator. (fig. 1) |
Below are the two maps that I created in decimal degrees (fig. 2) and in UTM meters (fig. 3). Click on the maps to enlarge them. For each map I had to create a ticked border with measured increments for the respective units along with a grid. The UTM map was in meters and the Coordinate map was in decimal degrees. I then added the five meter contour lines and study area feature class on top of the satellite imagery. Next I put a north arrow, scale and metadata (projections, data sources and author) to each map.
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| Map of The Priory in decimal degrees. (fig. 2) |
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| Map of The Priory in UTM (meters). (fig. 3) |
Discussion
In the next exercise when we are using these maps I believe that I will have all the necessary information and data that will be need to help me navigate The Priory. The satellite imagery will prove useful when looking for landmarks and getting my bearings.
Some problems that could come up include the fact that my contour lines do not have a reference line and this might be a problem with figuring out if certain areas are sloped upwards or downwards. Another problem could come from the satellite imagery which could make it hard to see where the exact point I am along with the fact that this imagery is not super up to date. The Priory could have changed in the time since the image was taken and I could have incomplete or false data that causes me to make an error in the next exercise.
Conclusion
These maps will be very useful in navigating The Priory with just the right amount of information. The two separate maps should prove useful when measuring distances and slopes. I hope the maps I made will give me everything I need to have when navigating in the subsequent exercise and not lead me to get lost.
Sources
Map of the UTM Zones from National Geospatial-Intelligence Agency: Link
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