1. Maps, Maps, Maps

2. Cartography The art and science of map making

3. Geographic Information Systems or Sciences (GIS)

4. GPS Global Positioning System 24 satellites orbiting the earth
Collects signals
Provides instant locational data

5. Map Scale How much of the earth should be depicted on a map???
Scale = The ratio of dist. on a map to the dist. on the ground, where both are measured in the same units.
3 types of scale:
Representative Fraction
Verbal Scale
Graphic Scale

6. Representative Fraction
The map distance to ground distance ratio is written as a simple fraction (e.g.,1:3,800,000 or 1/3,800,000) ex. 84 in atlas
1 unit (in.,cm.,etc.) on the map = 3,800,000 of the same unit on earth

7. Verbal Scale
Words instead of numbers express the scale. For example the representative fraction of 1:63,360 can also be expressed as “one inch to one mile” or 1 in = 1 mile
1 in = 63,360 in
63,360/12=5,280
1 in = 5280 ft
5280 ft = 1 mile
Thus 1 in = 1 mile

8. Graphic Scale

10. Map Projections
Projection - The scientific method of transferring locations on earth’s surface to a flat map

11. Types of Projections
Conic (Albers Equal Area, Lambert Conformal Conic) - good for East-West land areas
Cylindrical (Transverse Mercator) - good for North-South land areas
Azimuthal (Lambert Azimuthal Equal Area) - good for global views

12. Conic Projections (Albers, Lambert)

13. Cylindrical Projections (Mercator)
Transverse
Oblique

14. Challenges
When maps are projected, areas near the poles often are distorted the most. Distortion always occurs, Use 184 in your atlas to see what the 4 types are: 1. Shape - ex: Mercator is correct for Greenland while Eckert IV is distorted 2. Distance – ex: latitude lines near the poles compared to equator 3. Size – ex: Mercator is distorted for Greenland while Eckert is correct 4. Direction – Examine the differences in compasses for different maps