Sunday, February 16, 2020

Lab 1 - Creation of a Digital Elevation Surface using critical thinking skills and improvised survey techniques



Introduction
                The goal of the first Geospatial Field Methods lab activity was to collect the data to be used in the creation of a digital elevation surface to be created in a later lab exercise. This was accomplished using a variety of survey tools and sand boxes with pre laid out grids located on the eastern side of Phillips Science Hall on the lower portion of the University of Wisconsin – Eau Claire campus.  The collection of this elevation data was done in a small group with all group members contributing to the effort of data collection.  This lab was designed to hone our critical thinking ability as well as to give students more experience in common field techniques such as those used to survey a site and collect topographic data.

Methods
                To begin this lab exercise, the class left Phillips Science Hall and headed outside to the location of the sandboxes to be used for this lab.  These sandboxes had not been used in months and were therefore covered in many inches of snow and ice and required clearing before the lab exercise could begin.  As a result of the large amount of snow build up, some strings marking out the grid were dislodged and required fixing. With the sandbox ready, the group began adding snow to certain areas of the grid and carving out divots in the sand elsewhere to create a varied topography.


Figure 1. Preparing the sandbox

                With the grid complete and the desired amount of variance in topography reached, measuring and collection of elevation data then began.  To do this, a meter stick was used to measure the distance from the sand and snow to the level of the grid strings which represented sea level, or 0’ in elevation.  Data points were collected from the center point of each grid square and spray paint was used to mark which of the grid columns had already been collected as data was collected column by column originating from a 0,0 point in the lower corner. Each data point was collected to an accuracy of 5 millimeters and recorded in a table that had the same number of rows and columns as the grid over the sandbox had.
Figure 2. Collection of elevation data points

                Once elevation data for each of the grid squares had been collected, the group recovered the sandbox and came back inside to begin the process of data entry in an Excel spreadsheet.  This spreadsheet was formatted in a way with X, Y, And Z values that would best allow for the transfer of this elevation data into a GIS for the creation of a digital elevation model.
Figure 3. Examples of collected data in Excel spreadsheet

Discussion
                An important component of this lab was to develop and hone our ability to think critically both as an individual and as a group.  This lab contained little direction which therefore forced us to think about the steps that were necessary for us to take rather than simply follow directions that were provided by the professor. Although this proved to be a hurdle at first, the group came together to properly solve the problems that presented us. While the main problems of this lab exercise were solved and overcome, there were some other slight problems that could not be solved.  The first of these problems was the accuracy of the data collection as the grids were not perfectly aligned and measuring the height of the strings from the sand/snow was not always a perfectly accurate job as the meter stick would slightly sink into the sand or snow which meant we had to be very careful when measuring.

Conclusion
                Overall this lab was useful in developing our ability to think critically about a problem that we received little guidance to solve.  This lab also helped develop our problem solving and teamwork skills to solve a problem that would be found in the field.  The more experience in field work gained through the completion of this lab was also quite useful to my development as a student of geography.  The information gathered in this lab will be used for future lab exercises and the skills that have been gained in this lab will be used not just for future labs, but for future classes and employment as well.

Evaluation
Prior to this activity, how would you rank yourself in knowledge about the topic. 
4-A good amount of knowledge
Following this activity, how would you rate the amount of knowledge you have on the topic
5- I am an expert)
Did the hands-on approach to this activity add to how much you were able to learn.
4-Agree
What types of learning strategies would you recommend to make the activity even better?

       A larger sandbox to conduct this lab at a larger scale.

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