Maps: Two-dimensional, scaled representations of Earth surface - show spatial data (data with locational component)

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1 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)

2 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, religions Choropleth 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

3 Example of categorical map

4 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?

5 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

6 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)

7 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

8 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?

9 Map Scale The ratio of map distance to earth distance, measured in the same units smaller scale Sample Area Covered Fraction Scale Verbal Scale World 1:78,000,000 1 in = 1,250 mi No. America 1:36,000,000 1 in = 570 mi Central U.S. 1: 4,000,000 1 in = 64 mi AAA 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.

10 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?

11 Map Aggregation Percent of 1990 pop age 25+ with bachelor's degree 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) Data aggregated by State

12 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)

13 2004 Presidential Election Red = Bush; Blue = Kerry State results, by land area County results, by land area State results, by population County results, by population Source: M. Gastner, C. Shalizi, and M. Newman, University of Michigan

14 2004 Presidential Election Red = Solidly Bush (70% +) Purples = divided redder = Bush majority; bluer = Kerry majority Blue = Solidly Kerry (70%+) By land area By population Source: M. Gastner, C. Shalizi, and M. Newman, University of Michigan

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

16 Pattern Analysis: Density vs. Dispersion Which square mile has the higher density, (a) or (b)?

17 Various Pattern Arrangements What phenomena could explain the patterns shown in A, B, and C?

18 Quick mapping activity example of identifying changes in a spatial pattern, reasons for the changes, and consequences of these changes Coors Field 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).

19 Connections What kinds of things are symbolized by lines on this map?

20 Combination of climate, agriculture, and industry explains population density patterns Where are some patterns that illustrate this?

21 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?

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

23 Compare the Pacific coasts of North and South America Which places have analogous climates?

24 Spot any spatial correlations? Middle & South America Agricultural Regions (left) and Population Density (below)

25 An example of the importance of spatial thinking Christian

26 Diversity, exceptions, and edges can make for interesting case studies or SEMITIC examples (Afro-Asiatic Language Family) TURKIC (Altaic Language Family) IRANIAN (Indo-European Language Family)

27 Knowledge of cultural regions, boundaries, and transitions is necessary for understanding conflicts Turkey Syria Iran Jordan Iraq Ethnic Groups Saudi Arabia Kuwait 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.

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