1. GPS one day training
A quick and dirty introduction to GIS and
spatial data collection
Dr. Catherine Pfeifer

2. Objective of the day
You will know
● How a GPS works
● About diversity of GIS software to map your own data
● The advantages and disadvantages of different GIS software
You will be able
● to set a GPS right
● To collect data point and track your path with a GPS (to calculate
area)
● To map your own data in a GIS software
● To choose the GIS software that suits your situation and needs

3. Program of the day
● Playing a game to know each other
● Theoretical introduction to GIS
● Setting a GPS right
● How to collect points, lines (tracks), areas
● Downloading your data
● GIS software (Arc, QGIS, google earth)
● Map your data in your favorite GIS software
● Discuss your work and the difference between the
softwares

4. Program of the day
● Playing a game to know each other
● Theoretical introduction to GIS
● Setting a GPS right
● How to collect points, lines (tracks), areas
● Downloading your data
● GIS software (Arc, QGIS, google earth)
● Map your data in your favorite GIS software
● Discuss your work and the difference between the
softwares

5. Program of the day
● Playing a game to know each other
● Theoretical introduction to GIS
● Setting a GPS right
● How to collect points, lines (tracks), areas
● Downloading your data
● GIS software (Arc, QGIS, google earth)
● Map your data in your favorite GIS software
● Discuss your work and the difference between the
softwares

6. A theoretical introduction to GIS
● What is GIS and spatial data?
● What is a coordinate system and why is it
important?
● How to collect data? How does a GPS work?
● How to represent spatial data? An overview of GIS
softwares

7. What is GIS ?

8. Spatial data as representation of the real
world
● Spatial layer represents
one information that
can be overlaid for
analysis
● Two types of data
– Vectors (points,
lines, polygons)
– Grids

9. A theoretical introduction to GIS
● What is GIS and spatial data?
● What is a coordinate system and why is it
important?
● How to collect data? How does a GPS work?
● How to represent spatial data? An overview of GIS
softwares

10. Coordinate systems
What is a coordinate system?
A coordinate system is a reference system
used to represent the locations of geographic
features, imagery, and observations such as GPS
locations within a common geographic framework.
Coordinate system types :
• Geographic coordinate system
(global/spherical)
• Projected system (“making the world flat”)

11. Map projection

12. UTM projection
‘pseudocylindrical’ conformal projection (it preserves shape)

13. Concepts linked to coordinate system
● Datum : assumed shape of the earth
● Projection : none = geographic coordinate system
otherwise method applied for “flattening the world”
(example Mercator UTM)
● Coordinate format
– Degree minutes seconds, degree minutes, decimal
degrees (geographic coordinates)
– Meters, kilometers (projected coordinates)

14. Internationally used settings
Each country has national standards, but the international
standard is often default in many software.
● Datum :WGS 84
● Projection
– None for geographic
– UTM (use sheet 37 N for Ethiopia)
– (the national projection for Ethiopia is Adindan but we
recommend to use international standards)
● Coordinate format
– Decimal degrees (geographic)
– Meter (projected)

15. What to keep in mind
● GPS work generally with unprojected data
● If you are not sure what you are doing use
international standards
● Always write down what settings you used
● Ask a GIS specialist before doing “strange things”
like re-project or assign projection
A SMALL MISTAKE MAY LEAD TO DAYS OF
WORK FOR A GIS SPECIALIST AND IN THE
WORST CASE YOUR DATA IS USELESS

16. A theoretical introduction to GIS
● What is GIS and spatial data?
● What is a coordinate system and why is it
important?
● How to collect data? How does a GPS work?
● How to represent spatial data? An overview of GIS
softwares

17. Geographical Positioning System
● Uses satellites
to locate the
receiver
● With
smartphone
hybrid systems
(mobile and
wiki network)

18. What data can you collect with a GPS?
● Points (farmer's homestead)
● Tracks (lines, path traveled)
● Areas (farmer's field) works only on expensive
Garmin GPS

19. Settings in your GPS
● Must match with the settings you are going to use in
the GIS software
● Advice use WGS84 unprojected, coordinate in
decimal degrees
– All google geo-application use these settings
– It is also default in QGIS

20. A theoretical introduction to GIS
● What is GIS and spatial data?
● What is a coordinate system and why is it
important?
● How to collect data? How does a GPS work?
● How to represent spatial data? An overview of
GIS softwares

21. GIS software
● Full GIS solution
– ArcGIS (can be enhanced with DNR garmin)
– QGIS (with GPS plug-in)
– Google earth (with GPS feature on windows)
● GPS data download software
– DNR garmin (can be linked with GPS)
– Many others
● Others
– Drivers for gps
– Android tracking program (mytracks)