cartography (map-making) involves 5 design decisions – based on purpose of map projection

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Maps: Two-dimensional, scaled representations of Earth surface - show spatial data (data with locational component) Cartography (map-making) involves 5 design decisions – based on purpose of map Projection Simplification Scale Aggregation Type of Map (thematic* or reference)

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Maps: Two-dimensional, scaled representations of Earth surface - show spatial data (data with locational component). Cartography (map-making) involves 5 design decisions – based on purpose of map  Projection  Simplification  Scale  Aggregation - PowerPoint PPT Presentation

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Page 1: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Maps: Two-dimensional, scaled representations of Earth surface - show spatial data (data with locational component)Cartography (map-making) involves 5 design decisions – based on purpose of map

Projection Simplification Scale Aggregation Type of Map (thematic* or

reference)

Page 2: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

THEMATIC MAPS – depict characteristics of places

Categorical type - Depict areas that are different in kind- Use several distinct colors to show different categories

desert forest tundra

Examples: climates, religionsChoropleth type

- Depict areas that are different in amount- Use shades of similar colors to show different values

high value medium low value

Examples: population density, literacy rates

Page 3: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Example of “categorical map”

Page 4: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Example of “choropleth map”Human Development Index (HDI) Rankings

Includes GNI/PPP, Literacy, and Life Expectancy

Which regions have high HDI?Which regions have low HDI?Which places are exceptions?

Page 5: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Isoline type(Average Daily Solar Radiation)Lines connect points of equal value Dot Density type

(Wisconsin Acreage in Potatoes)

Each dot represents a frequency of mapped

variable

Page 6: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Proportional Symbol Map (Graduated Circle type)

Size of symbol varies in relation to frequency or intensity of the mapped

variable

Proportional Symbol Map (Flow Vector type)

Page 7: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Sample Map Projections

Mercator

Systematic methods of transferring a spherical surface to a flat map

Distortion must occur in either size, shape,

distance, or direction – all projections are

compromises

Robinson Polar

Page 8: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Equal-Area projections best where purpose is to compare distributions of a variable

between places(They distort shapes to make sizes correct.)

What impressions do you get from this map?

Page 9: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

smaller scaleSample Area Covered Fraction Scale Verbal ScaleWorld 1:78,000,000 1 in = 1,250 mi No. America 1:36,000,000 1 in = 570 miCentral U.S. 1: 4,000,000 1 in = 64 miAAA Colo map 1: 1,267,200 1 in = 20 mi

larger scale

Smaller-scale shows more land area in less detail. Used to show global patterns.

Larger-scale shows less land area in more detail. Used on local maps.

Map Scale The ratio of map distance to earth distance, measured in the same units

Page 10: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

The scale at which one analyzes an issue is critical DIA – Only major U.S. airport built since 1980

At the national scale, why did the location of this airport make sense?At the local scale, why was it necessary to locate the airport where it

is?

Page 11: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Percent of 1990 pop age 25+ with bachelor's degree

Data aggregated by State

Map Aggregation The level of detail for dividing a thematic map into

geographic units

Ranges from coarse divisions

(e.g., by countries) to fine divisions (e.g., by zip

codes)

Page 12: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Percent of pop age 25+

with bachelor's degree (1990)

Note what information is lost at higher levels of

aggregation

Aggregated by State

(northeast close-up)

Aggregated by County (WV, MA)

Page 13: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Source: M. Gastner, C. Shalizi, and M. Newman, University of Michiganhttp://www-personal.umich.edu/~mejn/election/

State results, by land area

County results, by land area

State results, by population

County results, by population

2004 Presidential Election Red = Bush; Blue = Kerry

Page 14: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Source: M. Gastner, C. Shalizi, and M. Newman, University of Michiganhttp://www-personal.umich.edu/~mejn/election/

2004 Presidential ElectionRed = Solidly Bush (70% +)

Purples = divided … redder = Bush majority; bluer = Kerry majority

Blue = Solidly Kerry (70%+)

By land area By population

Page 15: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Spatial Thinking(Phil Gersmehl, Research in Geographic Education, 2006)

Page 16: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Pattern Analysis: Density vs. Dispersion

Which square mile has the higher density, (a) or (b)?

Page 17: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Various Pattern Arrangements

What phenomena could explain the patterns shown in

A, B, and C?

Page 18: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Quick mapping activity – example of identifying changes in a spatial pattern, reasons for the changes, and consequences of these changes

With a partner, map the following (on the same map):

1. Use a diamond symbol for the cities in which there was a Major League Baseball team in 1952 (16 teams).

2. Use a different symbol for the locations of MLB teams in 2007 (30 teams).

Coors Field

Page 19: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Connections

What kinds of things

are symbolized by lines on this map?

Page 20: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Combination of climate, agriculture, and industry explains population density

patternsWhere are some patterns that illustrate

this?

Page 21: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Denver metro area

How does this map illustrate the aura

or zone of influence for

Denver?

How are hierarchies

symbolized on this map?

For which kinds of services does Denver’s aura

extend beyond this map?

Page 22: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Where could you define a region of “Elvis-lovers”?Where are the exceptions?Where are the outliers?

Page 23: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Compare the Pacific coasts of North and

South America

Which places have

analogous climates?

Page 24: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Spot any spatial correlations?

Middle & South America Agricultural Regions (left) and Population Density

(below)

Page 25: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Christian

An example of the importance of spatial thinking

Page 26: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

TURKIC (Altaic Language Family)

IRANIAN (Indo-European Language Family)

SEMITIC (Afro-Asiatic Language Family)

Diversity,exceptions,and edgescan make

forinteresting

case studiesor

examples

Page 27: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection

Iraq’s population is 29 million: sixty percent are Shi’a Arab, mostly in the south.

Sunni Arabs are concentrated in the center (western Iraq is sparsely populated).

Over 4 million Iraqis in northern Iraq are Kurdish. Baghdad is a transition zone.

Saudi Arabia Kuwait

Iran

Jordan

Syria

Turkey

Iraq Ethnic Groups

Knowledge of cultural regions, boundaries, and transitions is necessary

for understanding conflicts

Page 28: Cartography  (map-making) involves 5 design decisions – based on purpose of map  Projection