UCT GIS Labs

1. What is Geospatial Data?
Everything Happens Somewhere
http://geography.oii.ox.ac.uk/?page=geographic-knowledge-freebase

2. Everything Happens Somewhere
As a result, practically all data
has a spatial attribute (US
Office of Management and
Budget, 2002)
- Explicit (coordinates,
addresses)
- Implicit (landmarks, directions)
- Inferred (creators,
researchers, referees)
http://geography.oii.ox.ac.uk/?page=mapping-edits-to-wikipedia-from-africa

3. Inferred Spatial Context
Even if the subject at hand is not
directly spatial, odds are
good that it has spatial context
- Where is this subject being
created/studied?
- Any important places with
references to this subject?
- Any important researchers/centres
of excellence?
- Who is looking for information on
this subject? http://geography.oii.ox.ac.uk/?page=the-location-of-academic-
knowledge

4. Sourcing Spatial Data
Existing spatial data sets can be found locally (in libraries and
data repositories) or via the Web
Ready to Use:
• Satellite imagery
• Climatic Data
• Census Data
• Elevation models
Reference:
• Topographic Map
Series
• Gazetteers
• Google Earth
Local names for “cheap” beer sourced
via Twitter
http://www.floatingsheep.org/2014/04/new-book-
chapter-on-geographies-of-beer.html

5. Sourcing Spatial Data: The Web
Google search for mosquito densities
leading to MosquitoMap.org

6. Ready to use data
Underlying dataset of land
cover classifications can
immediately be used in
overlay analysis

7. Reference
Data
The image of Pyongyang in
1950 provides context and
meaning to a human
observer but cannot be
directly queried or used in a
GIS analysis. Features
would need to be traced off
(digitized) into separate
layers.

8. Creating Spatial Data:Geocoding
By using explicit coordinates, or looking up addresses or
landmark locations referred to in reports and papers it is
possible to create spatial attributes for data in practically
any discipline.
Wireless Access Points, Jagger Library, 4th Floor
via ICTS Website

9. Creating Spatial Data:
Geo-tagging Audiovisual Data
It is also possible to geocode
audio and video records:
• Through coordinates
captured and stored by
recording devices (such as
modern smartphones and
GPS data loggers)
• Retroactively by matching
landmarks in the
background of photographs,
postmarks on postcards,
references to locations in
interviews or songs.

10. Map
Visual orientation is the most
common operation
• “make a map of the study
area”
• “make a context map
showing the study area
relative to
landmarks/roads/provincia
l boundaries”
Sandy Shell, Oromo Slave First
Passage Journal Analysis Study
Area

11. Analyse
Mapping data is the first action,
but by analysing it using spatial
functions you are able to:
• append information from the
surrounding spatial
environment (overlay)
• analyse the spatial distribution
pattern (geo-statistics)
• model or predict occurences
(envelopes)
Sandy Shell,
Oromo Slave
First Passage
Journeys

12. Share
Once you have gone
to the effort of
spatially locating
data, creating
maps or derivative
data
SHARE IT!
The more spatial data
available, and the
easier it is to
reach, the better it
is for future
research.
ArcGIS.com Map Gallery & MapTube.org

13. Reference your data
Spatial data is just like
any other sort of data
• It needs to be referenced/acknowledged
• It needs metadata in order to be assessed against future mapping
or analytical needs (scale, date, original source, pre-processing)

14. How?
Desktop
Use a GIS package on your
PC/Mac/Tablet/Phone
• Free Desktop
Quantum GIS, Google Earth,
uDig, MapWindow
• Expensive Desktop
ArcGIS, Autodesk, Illustrator
Plugins, Ortelius, MapDraw
Quantum GIS & ArcGIS Interfaces

15. How?
Web Based
Free Web
Google Fusion Tables,
Map Engine
OpenStreetMap
GNSS (Geographic
Name Servers)
Expensive Web
ArcGIS Online, WeoGeo,
MangoMap
OpenStreetMap.org & MangoMap.com

16. UCT GIS Lab
Nicholas Lindenberg
Thomas Slingsby
Tel: 021 650 3917
Room 5.25 G.H Menzies Building