Preparing the Data

The following Skill Drills use the knowledge you have learned in previous courses, including Geospatial Concepts (GSP 101) and Geographic Information Science (GSP 270). Therefore, the instructions do not contain many step-by-step details. You should refer to previous coursework if needed. Registered students may also post questions on the weekly Q&A Discussion Forum on the Canvas LMS.

Skill Drill: Collecting Elevation Data Using a GPS Receiver

Use Google Maps or the HSU Campus map to choose a location on campus, approximately 1 hectare, that contains significant changes in elevation. For example, the area between Founders Hall, the Upper Playing Field, and the Kinesiology & Athletics Building would be an ideal area. It contains varying elevation with few GPS signal obstructions. Alternatively, you may choose another suitable location either on or off campus. Use the map to make a rudimentary data collection plan. Decide where you will begin your data collection and where you will end. Plan how and where you will travel during data collection. For the best results, your waypoints should be distributed as evenly as possible across your area of interest. Avoid clustering your data points if possible. A useful method for doing this is to mark a waypoint about every 10 or 20 strides. Using a GPS unit, collect between three hundred and five hundred waypoints with elevation data. Use what you have learned in Geospatial Concepts (GSP 101) or other previous courses to optimize the accuracy and efficiency of the GPS receiver. Specifically, you should make sure your GPS Unit is WAAS enabled. Also be aware of any obstructions. For this lab, you may team up with some of your fellow students to collect waypoints if you wish. It may be helpful to divide the work between lab partners and merge the data points into one shapefile in ArcMap. You may check out a GPS unit from the HSU Library reserve desk. Students are allowed to check these units out for four hours at a time.

An image of GPS data over Redwood Bowl
In this image, waypoints were collected at Redwood Bowl and surrounding regions. The aerial photograph was obtained from the USGS Earth Explorer. Click to view a larger size.