Transcript Hall of Luxembourg

Alex B. Owusu
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Geographic Data
Visualization
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Geovisualization
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Showing or representing geographic data
Quantitative
Qualitative
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How do you represent geographic data to
communicate exactly what you want to
Making the representation for people to see
without explanation
Intuitive
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Line
Point
Polygon
Colours
Area
Surface
Description
Objectives
 The main components, or building blocks, of a map
 The qualities of a map that are important in communicating information to
map users
 The types of maps that can be developed to visually and quickly
communicate information to an audience
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Mapmakers need to understand…
• The objective(s) of the map (the message)
• The people who may use the map (the audience)
• The data that will be displayed in the map (the info
• rmation available)
• The use of graphics software for displaying map information
• The final format of the printed or digital version of the map (the
product)
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Bibliography
M.J. Kraak and F. Ormeling (2009): Cartography: Visualization of Spatial
Data. Prentice Hall
T. Slocum (2003): Thematic Cartography and Geographic Visualization.
Prentice Hall.
Teaching and learning methods
Lectures, lab work, self-study on articles in magazines
Required infrastructure
Class room with computer projector, computer laboratory with GIS software
and data
Assessment
To pass this module, the students are required to complete all exercises;
successfully present the final project and pass the written exam
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•Symbology
•Direction
•Scale
•Legend
•Locational inset
•Neatline
•Typography
•Color and contrast
•Ancillary information (caveats and disclaimers)
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• The art of expression
• Using graphics and text
to convey meaning
• Most GIS packages offer
a robust suite of
symbology choices
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 The representation of map figures to their on the
ground equivalents
 A key part of most maps
 Several different approaches
 Graphical
 Equivalent
 Proportional
http://www.proza.ru/pics/2011/08/10/103.jpg
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• People associate colors of mapped features with events,
emotions, and socio-economic status
• Although men and women react similarly to color, some
reactions may vary depending on culture (Valdez & Mehrabin
1994)
• How do you react to different colors?
CMYK
http://image-24.ru/wp-content/uploads/2010/06/rgb.gif
Red, Green, Blue - Additive colors
http://t1.ftcdn.net/jpg/00/12/11/50/400_F_12115010_WVSCD8xd8l
samF2GU7p6QXxvKrdpn11A.jpg
Cyan, Magenta, Yellow -Subtractive colors
http://docs.huihoo.com/mapserver/5.2.1/_images/carto-elements.png
http://www.lib.utexas.edu/maps/americas/middleamerica.jpg
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Audience- are they all familiar with your study
area? Is an inset required?
Will others need to track your sources ?
Do you need to record where the map is stored?
Are revisions expected or will the study area
change (date)?
Title, scale, author, and north arrow are safe bets
Publication outlets may have their own guidelines
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Wrong audience
Omitting a necessary element
Too much clutter (symbology)
Too much detail (annotation)
Plotter or printer produces something different
than what you see on the screen
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How to Lie with Maps (Monmonier 1996)
Drawing the Line, Tales of Maps and
Controversy (Monmonier 1995)
Models of reality
Many simply accept maps at face value
Be discriminate in your appraisal and
interpretation of maps
Be clear and ethical in your creation of maps
PROBABILISTIC MAP
OF SEISMIC RISK
Map from Atlas of natural and technological hazards and risks of emergencies in the Republic of Kazakhstan (2010)
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Reference
Topographic
Dot
Picture Symbol
Graduated Symbol
Multivariate symbol
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Network
Flow
Isopleth
Reference
http://www.luxembourg.co.uk/pics/railnetw.jpg
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Choropleth
Dasymetric
Area qualitative
Stepped surface
Hypsometric
Reference
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HTML embeds PNG, JPEG and GIF
Animation possible with GIF
Drawing extensions with SVG (XML)
Otherwise, need JAVA or FLASH
GIS data can be web enabled with on-line
products such as Arc Server/IMS and
GeoMedia Web Map, MapInfo Envinsa
Map open source tools
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[Isopleth, Stepped Surface, Hypsometric]
Gridded fishnet
Realistic perspective
Hill-shaded
Image map
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Multiple views
Animation
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Moving map
Fly thru
Fly by
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Unload interaction functions to web client
Build and make visible 3D models
VRML established as 3D web equivalent of
HTML
GeoVRML is geographically enabled VRML
GML, X3D now available
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Public domain Web tools (CosmoCreate and Player)
Works for both immersive and passive displays
Symbolization at feature level, any dimension object
Integrated environment to develop, test and distribute
cartographic methods
Combine traditional cartographic portrayal techniques,
animation, and 3-dimensional display
Importance of nodes and georeferencing Worlds
(GeoVRML 1.0)
Incorporates visual field depth via proximity sensor
and zoom
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Focus on your audience
Understand your data
Define your representation
Highlight your key points
Use marsh up where you can
Give spatial reference
Do not obscured other information
Don’t create information overload
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http://colorbrewer2.org/
Earth.google.com
Create animation for presentations – Using AVI
– Time animation or layer animation
Use 3D where necessary
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3 SECTIONS
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A 20 SHORT ANSWERS
MR GERALD YIRA 2 QUESTIONS ANSWER
1
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SECTION C: 2 QUESTIONS ANSWER 1
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Maps are projected and not drawn in order to
minimize distortions. Discuss five properties of
map that are likely to be distorted when maps
are drawn?
Explain any three of the following:
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Vector Data
Raster Data
Dissolve
Buffer
Merge
You are contracted to create a digital map from a
hard copy map. Explain exactly how you will
execute the exercise to its logical conclusion.
 a. Explain the term Geoprocessing
b. Use a flowchart to model how you will perform
spatial analysis to determine watershed areas that
are likely to suffer from pesticides contamination.
 Explain any five Errors that are likely to occur
during GIS data creation. How do you avoid them?
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