K-12 Education: Integrating GIS and GPS April 1, 2008

Global Positioning Systems GPS is a revolutionary navigation system o 24 satellites orbiting the earth o Provide location within metres or less anywhere on the globe. o Now available in many cars as an option o Created and operated by the US Department of Defense

More about GPS satellites Constellation of 27 satellites o (24 active + 3 spare) Orbit 12,600 miles above earth o (10,900 nautical miles) Satellites in 12 hour orbit First satellite launched in 1978, 24 th became operational in 1994 Selective availability was removed in May, 2000 o Handheld receivers are now much more accurate

How does GPS work? Measuring distance by measuring time Satellites send coded signals indicating their position in space and the exact time the signals are being sent Receivers use the time it takes signal to travel from satellite to receiver to determine distance from satellite to receiver Information from multiple satellites is used to determine position through ‘triangulation’

How does GPS work?

More about GPS receivers A GPS receiver's job is to locate four or more satellites, figure out the distance to each, and use this information to deduce its own location. o Hand-held receivers for recreational use with accuracy of metres o Vehicle mounted receivers for navigation or agricultural use with accuracy of < 1 metre o Backpack or tripod mounted receivers for surveying use with accuracy of 5 – 10 centimetres

More about GPS receivers Receivers require clear line-of-sight; thus, they will not work indoors or where tall objects obscure the sky

What’s so cool about GPS? GPS units o Can be used as a digital compass o Can be used to determine ground speed o Can store landmarks (locations) o Can be used for dynamic routing o Can be used for mapping applications

Applications of GPS In-vehicle Navigation (car, boat, airplane) Asset Management Construction Geologic Research & Mining Military Navigation and Operations Mapping & Surveying Precision Agriculture Public Health Public Safety Wireless Communications

GPS in the classroom

Integrating GIS and GPS Collect a series of latitude and longitude points using GPS receivers o add them into an existing digital map Skills in o data collection/creation o GPS reading o observation Digital photos

Geocaching A great way to introduce students to GPS o Teach latitude/longitude o Take advantage of the wonderful features and capability of your GPS unit An entertaining adventure for GPS users o Individuals and organizations all over the world have set up caches and shared the locations of these caches on the Internet o Participate in a cache hunt to find an existing cache or create your own

Classroom projects There are many ways you can incorporate GPS data collection into your classroom Possibilities include o a virtual trail in your area o mapping the locations of litter and garbage cans to determine if there is a relationship, and if more garbage cans are necessary o collecting data about tree types and locations on school grounds and beyond o gathering water samples from a local stream and taking GPS readings at each location o orienteering/navigating (hiking, boating, biking, driving)

Getting started GPS units - Garmin eTrex o perfect for introducing students to field data collection and the power of GPS o industry's smallest and lightest handheld GPS receiver o sleek waterproof housing will fit in your shirt pocket and weighs only 5.3 ounces o a 12 channel parallel receiver, differential ready, with a built-in patch antenna o runs for 22 hours on just two AA batteries Pencil, clipboard, paper

Getting started - additions Connection cables for your GPS units o Allow you to download data from your GPS unit to your computer o Free extension available to convert to shapefile Local data o Create a base map for viewing the data you have collected o Provides context and other features for GIS analysis with ArcView Digital camera

Collecting data Collect data in the field using GPS o Write down point coordinates and additional data observations - OR - o Use tracking function of your unit to store points, lines, or polygons, and write down additional observations

Using the data you collect Manually enter the coordinates and observations into a table (Excel, etc.) o Save as a.dbf file o Add to ArcView o Use “Add X,Y” or “Add Event Theme” to create points on your map - OR - Use your GPS unit cable to download the data from the unit to your computer

For more information… Books from ESRI Press o Integrating GIS and the Global Positioning System  Karen Steede-Terry o Fun with GPS  Donald Cooke o Community Geography: GIS in Action  Kim Zanelli English and Laura S. Feaster

For more information… Lessons on the ESRI Canada website o o Integrating GIS and GPS (ArcView 3.x) o Exploring Pukaskwa National Park (ArcView 8.x/9.x) Garmin website o Trimble GPS o How stuff works o