Digital Elevation Surface Survey

Introduction

The purpose of this assignment was to create a surface terrain and survey this area without standard survey techniques.  In order to do so, we had to come up with a suitable coordinate system and survey technique that would account for our study area.  Geospatial and critical thinking were essential because only a tape measure, rope and a meter stick were available to conduct the survey.  Unfortunately, migraines don’t take class assignments into consideration and I wasn't able to attend the actual survey.

Methods

Because I was sick and unable to attend the survey, so I am using the data of my group members Phil and Tonya.  The first step in this assignment was to construct the terrain (Figures 1 and 2).  Our terrain included a ridge, hill depression, valley and plain.  This was done by hand in our study area which was planter box in the courtyard of Phillips.

Figure 2- Creating the terrain

Figure 1- Creating the terrain

The next step was to set up the coordinate system for the survey.  Before the physical collection of the survey, we had discussed what the best coordinate system would be.  We decided that the short end of the planter box became the X Axis and the long edge became the Y Axis.  When it came time to collect the X and Y measurements, my group members decided it would be best to use a mobile X Axis for accuracy.  A meter stick was taped to a larger stick for the mobile X axis.  Because the mobile X axis would be gliding on the outer wooden edges of the planter box, all elevations had to be lower than this height.  Phil and Tonya had to “shave” down some of the previously formed ridges and hills.  The Y axis also had a tape measure taped to the edge of the planter box.  This helped not only for an accurate Y measurement, but also an X measurement because the mobile X axis could be measured with the Y Axis so it was completely straight.  The origin of our coordinate system was very traditional at 0,0.

X and Y measurements were taken at 5 centimeter intervals where the surface had in increased amount of terrain features and 10 centimeter intervals where the surface was smoother.  As seen in image 3, once the measurements were taken for the length of the X axis, the mobile axis was shifted up to the Y axis.  The Z measurements were taken with a meter stick vertically placed along the terrain (Figure 4).  This was done for the entire study area.  The measurements were recorded onto an Excel spreadsheet.

Figure 3- Collecting X, Y and Z coordinates

Figure 4- Collecting X, Y and Z coordinates

Figure 4- Excel Spreadsheet

After the survey was conducted, the measurements were digitally imported into the Excel spreadsheet (Figure 4).  All Z measurements were in negative numbers, so 17 was added to each measurement.  The number 17 was added because the lowest Z measurement was -16.  This ensured all measurements were a positive number which allows for easier calculations.

Discussion

I am really disappointed that I was not able to help with the physical collection of our data.  Being absent from the most important part of an activity really shows how important this aspect of the assignment is.  My group members would not have struggled as much if I would have been there because it is a hands-on activity and as they say, “more hands make for lighter work.”  Also, it is hard to comprehend the data because I was not present in the collection.  This can be thought of in ways outside of just this assignment.  Data interpretation is essential in geography because it can manipulate the meaning of the data if it is misinterpreted.  It is essential in this activity to be present to really comprehend the importance of Geospatial thinking.  Without being physically present in the data collection, I missed out on the problems and wasn't able to suggest ideas to overcome these problems with the survey.

Conclusion

The biggest thing I have taken away from this assignment is the great necessity of being physically present in data collection of our study or survey.  Without being present, you can miss important aspects to the data and you are not able to solve problems with group members.  I look forward to revisiting our study area and hopefully the weather will cooperate so our surface terrain is similar to the state we left it.