1. Unit 1: Maps & Projections

2. Function of a Map Two purposes As reference tools
To find locations, to find one’s way
As communications tools
To show the distribution of human and physical features

3. Scale Small scale – shows a large area without a lot of detail
Ratio/fraction – shows the ratio of distance on a map compared to the real earth measurement.
Bar/graphic – shows the ratio of the distance on the map to the distance on the earth
Written – describes relation between map and Earth in words
Small scale – shows a large area without a lot of detail
Large scale – shows a small area with a lot of detail.

4. Scale

5. Questions
1. In what way do you most often use a map? Reference or communication?
2. Which map would have the largest scale?

6. Globe 3d representation of the earth
Advantage: provides a way to view the earth as it travels through space
Disadvantage: Can only see half of it at one time

7. Maps 2d representations of selected parts of the earth’s surface
Advantage: easily portable and can be drawn to any scale needed
Disadvantage: distortion occurs when as the earth’s surface is flattened to create a map

8. Types of Maps
General reference or topographic map -natural and man-made features on the earth
Thematic – emphasize specific kind of information
Navigational – help users plot a course through water or air.

9. Political
Shows features on the earth’s surface that humans have created.
Cities, states, provinces, territories, and countries
Physical
See types of landforms and bodies of water in a specific area.

10. Thematic
Climate, vegetation, natural resources, population density and economic activities
Qualitative - use colors, symbols, dots or lines to see patterns
Cartograms – info about a country based on data other than land area.
Flow-line – illustrate movement of people, goods, ideas, and animals,

11. Questions
3. Which are you more likely to use, a physical map or a political map? Explain your answer.
4. Give one example of when a thematic is helpful and one example when it is not.

12. Map projections
A way of drawing the earth’s surface that reduces distortion caused by presenting a round earth on flat paper.
A cartographer will reduce some types of distortion by using different types of map projections
Distance, shape, direction, or area/size may be distorted.

13. Planar Projection Projection on a flat surface.
Also called Azimuthal which shows the earth so a line that from the central point on the map gives the shortest distance between two points.
Size and shape are distorted.

14. Conical Projection Projected onto a cone
Shows shape fairly accurate and used to show landmasses that cover large areas going east and west
Distorts landmasses at the edges

15. Cylindrical Projections
Projection onto a cylinder and shows the entire earth on one map.
Three types
Mercator
Homolosine
Robinson

16. Questions 5. Why are map projections needed?
6. What 4 things are distorted in a map projection?

17. Mercator
Shapes of continents are distorted at the poles and somewhat compressed near the equator

18. Homolosine Oceans are divided
Shows accurate shapes and sizes of the landmasses but distances on the map are not correct.

19. Robinson
Shows entire earth almost true to sizes and shapes of continents and oceans.
Shapes of the landforms near the poles appear flat.

20. U.S. Land Ordinance of 1785 Township and range system
Township = 6 sq. miles on each side
North–south lines = principal meridians
East–west lines = base lines
Range
Sections

21. Township and Range System

22. Contemporary Tools Geographic Information Science (GIScience)
Global Positioning Systems (GPS)
Remote sensing
Geographic information systems (GIS)

23. Questions
7. Which cylindrical map projection shows the world most accurately?
8. Discuss with your neighbor the last time you used GPS?