1. Obj 1.5: Use and Interpret Maps
September 14, 2017
Obj 1.5: Use and Interpret Maps

2. What is a map?
Maps are used to represent and identify spatial patterns and processes at different scales.
A small scale map shows the largest area

7. Types of Maps
Reference Maps: shows the location of the geographic areas for which census data are tabulated and disseminated. The maps display the boundaries, names and unique identifiers of standard geographic areas, as well as major cultural and physical features, such as roads, railroads, coastlines, rivers and lakes.
Can be a political map (shows governmental boundaries of countries, states, and counties, the location of major cities, and they usually include significant bodies of water.) or a physical map (shows the same data found on a political map, but their primary purpose is to show landforms like deserts, mountains and plains.)
Thematic Maps: designed for a specific purpose
Choropleth Map
Dot Density Map
Graduated Symbol Map
Isoline Map
Cartogram

8. Thematic Maps

9. Choropleth Map
•Applies distinctive colors to represent different quantities or densities
•Typically on a map of a formal region (political)

10. Dot Density Map Shows distribution using a concentration of dots
Each dot represents the same quantity
Used for population density

11. Graduated Symbol Map •Portrays numerical quantities
•Symbols are drawn proportional to the value at that location

12. Isoline Map
•Used to portray quantities that vary smoothly over a given area
•Joins locations with the same value
•Used for climate variables

13. Cartogram
Deliberately distort map shapes to achieve special effects

14. Map Projections

15. Map Projections
Because the earth is a sphere and maps are flat, all maps distort some aspect of reality
The process of showing a curved surface on a flat surface is done using a map projection
Cartographers, or map makers, decide whether they want to preserve area, shape, distance, or direction on their map accurately, knowing that other elements will have to be less accurate as the earth is “flattened” on their map
Why are we changing maps?

16. Map Projection chart
Complete the Map Projection Chart using your text, review book, and the Internet. Put your completed activity in your Unit Portfolio. You may work with a partner on this activity. The projections are Conic, Robinson, Peters, and Mercator.
Purpose
Strengths
Distortion
Projection
Navigation
Directions are shown accurately
Land masses near the poles appear large
Spatial Distributions Related to Area
Sizes of land masses are accurate
Shapes are inaccurate, especially near poles
General Use in Midlatitude Countries
Size and shape are both close to reality
Longitude lines converge at only one pole
General Use
No major distortion
Area, shape, size, and direction are all distorted