CARTOGRAPHIC COMMUNICATION

TWO TYPES OF MAPS:

Reference Maps- Show locations of

places and geographic features

- Absolute locations

What are reference maps used for?

Thematic Maps- Tell a story about

the degree of an attribute, the pattern of its distribution, or its movement.

- Relative locations

What are thematic maps used for?

GRADUATED CIRCLE MAPS OR PROPORTIONAL SYMBOL shapes of different

sizes to show where and how much

Larger the circle = more phenomenon

Single variable Population, median

income, wheat production, or average land value

Swine Flu

DOT MAP

A single or specified number of occurrences is represented by a dot

Good for suggesting spatial pattern, distribution, and dispersion

Poor at showing precise valueCrime Map

COMMERCIAL WIRELESS SIGNALS

ISOMETRIC/ISOPLETH/ISOLINE MAP

Features isolines that connect points registering equal values of whatever is being mapped.

Isoline show where there is a uniform occurrence

Poor at showing information that might be patchy

Where Pennsylvanian students prefer to live

Where Californian students prefer to live

Perception of Place

CHOROPLETH

Shows data in a predetermined unit.

Each unit is shaded to represent how much of an item in the borders

Can give a false impression of abrupt change

Smaller units are better than larger (1-5) is more accurate than (1-50)

Election Results

CARTOGRAM

Uses statistical data to transform a space so that the largest unit on the map is the one showing the greatest statistical value

Gives a good visual representation of quantity but not good at communicating exact numbers

MOST THEMATIC MAPS HAVE: Simplification-

What has the cartographer chosen to keep Why are things left out?

Symbolization What do the symbols add to the meaning? Does it look attractive?

Classification Thematic maps use categories Equal interval or set values

Induction Information is under the surface or hidden Linked to classification

Centering- what is placed in the center of the map shows cultural/artistic value

SIMPLIFICATION

SIMPLIFICATION

SYMBOLIZATION

SYMBOLIZATION

SYMBOLIZATION

SYMBOLIZATION

CLASSIFICATION

CLASSIFICATION

CLASSIFICATION

INDUCTION

CENTERING

CENTERING

CENTERING

SCALE

SCALE

MESSAGE/ART

Message/Art