GEOG 181 - Designing Effective Maps
Weikai Tan
Estimated reading time: 4 minutes
Table of contents
- Week 1: An Introduction to Maps
- Week 2: History of Cartography
- Week 3: Size and Shape of the Earth, Geographic Coordinates
- Week 4: Map Projections
- Week 5: Issues Related to the Accuracy of Maps
- Week 6: Principles of Map Design
- Week 7: Mapping Quantitative Data
- Week 8: Choropleth Maps and Classification
- Week 9: Mapping Terrain
- Week 10: Online Mapping and the Geoweb
- Week 11: Maps and Society
- Week 12: Future Directions in Mapping
Week 1: An Introduction to Maps
“A map is any concrete or abstract representation of the features that occur on or near the surface of the earth or other celestial bodies.”
– (Campbell, 1998)
“Any geographic image of the environment.”
– (Muehrcke, 1978)
Map can be classified in two big category: mental maps, and map based on collected data.
Week 2: History of Cartography
“The science of making any map, embracing all phases of work from surveying to map printing”
– Cartographic Office of the United Nations Organization, 1949
“Cartography is the theory, technique and practice of map making and map use”
– Kolacny (c. 1969)
“Cartography is the art, science and technology of making maps together with their study as scientific documents and works of art”
– British Cartographic Society (recent)
Week 3: Size and Shape of the Earth, Geographic Coordinates
This uneven surface can be represented by a geoid.
On the almost spherical Earth, we can specify a location using latitude, longitude, and elevation.
We need a datum to determine exact latitude and longitude at a point.
Week 4: Map Projections
When we transfer features from the curved surface of the Earth onto a flat map, we are creating a map projection.
There are four types of projections: equal area projections, equidistant projections, conformal projections, azimuthal projections.
Also the Universal Transverse Mercator (UTM) projection
Week 5: Issues Related to the Accuracy of Maps
Note the difference between accuracy and precision; error and uncertainty.
We can use math to find the extent of distortion on a location: \[ \large \text {Scale factor} = {\text {Local Scale} \over \text {Principal Scale}} \]
Week 6: Principles of Map Design
The process of cartographic abstraction is supported by a number of map design techniques.
“Cartographic representation is making the world understandable through systematic abstraction that retains the iconicity of space depicting space.”
– MacEachren, A. M., & Kraak, M. J. (2001). Research challenges in geovisualization. Cartography and geographic information science, 28(1), 3-12.
Week 7: Mapping Quantitative Data
Describing Spatial Data
Level of measurement:
- Nominal: or categorical.
- Ordinal.
- Interval: the distance between values is meaningful. From questionpro: “Interval data, also called an integer, is defined as a data type which is measured along a scale, in which each point is placed at equal distance from one another.”
- Ratio: a quantified difference between values with an absolute zero point. An example from small arms survey.
Week 8: Choropleth Maps and Classification
Choropleth maps use a sequence of colour shades to represent categories of data for a given area of geography.
Overview of Choropleth Mapping
A choropleth map represents data not as individual points.
In class, we examine How long will YOU live?. Then How does your nation rank?.
Three main colour schemes are:
- Qualitative.
- Sequential.
- Diverging.
Selecting a Data Classification Method
The purpose of classification is to simplify data through creating groupings of similar data points.
Classification Method
- unclassified data.
- equal interval method.
- quantile (equal count) classification method.
- natural breaks classification method.
- unique values classification.
Week 9: Mapping Terrain
Topographic Maps and Symbols
Topographic maps: show a selection of features on the land surface.
Representing Continuous Surfaces
Type of Contours
- Index contours
- Intermediate contours
- Supplementary contours
- Depression contours
Landscape Visualization
The visualization of landscape through drawing techniques has become somewhat of a relic of traditional paper cartography.
- hachuring: wiki
- addition of lines, shading, and hachuring
- Hill shading
- 3-D Approaches to Visualizing Terrain
Week 10: Online Mapping and the Geoweb
Some terms:
- simple static maps
- basic interactive maps
- interactive maps with data query
- participatory/Web 2.0
Definition of Geoweb (Lake & Farley, 2007):
“Integrative, discoverable collection of geographically related web services and data that spans multiple jurisdictions and geographic regions”
Week 11: Maps and Society
Maps have power.
Military applications. Geospatial Revolution 1
Public Participation GIS (PPGIS) can be considered as:
“A variety of approaches to make GIS and other spatial decision-making tools available and accessible to all those with a stake in official decisions.”
– Schroeder, P. (1997). A public participation approach to charting information spaces. In ACSM/ASPRS Annual Convention and Exposition Technical Papers (Vol. 5, pp. 244-253). Seattle, WA: ACSM/ASPRS.
Week 12: Future Directions in Mapping
After taking GEOG 181, one can take 281, 381, 481, which is GIS stream. Or 271, 371, 471, which is remote sensing stream. Or 310, 410, which is surveying stream.