1. Map Projections

2. Map Projections
Putting a sphere on a flat surface messes up certain realities:
Distance
Direction
Shape
Area
Each map keeps one or two things true (pros), but the others are not accurate (cons).

3. Mercator Pros: Direction Cons: Shape Distance Area
Africa is actually 14 times larger than Greenland!

5. Robinson
Pros: Cons:
Better area Direction and shape Distance

7. Goode homolosine
Pros:
Shape
Area
Cons:
Direction
Distance

9. Latitude and Longitude

10. Hemispheres

11. Hemispheres

12. The Earth’s Grid
Any spot on Earth can be plotted with latitude and longitude.
Lines of latitude run east-west
“Lateral” means “side-to-side” (lateral pass)
Also called parallels
Measured in degrees of N or S
0° latitude is the Equator
90° N is the North Pole
90° S is the South Pole

13. Latitude
Measure North
Equator
Measure South

14. Upper Latitudes
Lower Latitudes

16. Longitude Lines of longitude run north-south
“All lines of longitude are long”
Also called meridians
Measured in degrees of E or W
0° longitude is the Prime Meridian
Runs through Greenwich, England, just outside London
180° E/W is the International Date Line

17. Longitude
180° W
180° E 0°
Measure West
Prime Meridian
Measure East

20. 35º N
34º 5’ N
34º N
18º E
19º E
18º 25’ E

21. The Earth’s Grid
A specific location uses N or S and W or E for each coordinate pair
Three ways to show coordinates:
Degrees, minutes, seconds: 30°, 15’, 45” N; 54°, 20’, 10” W
1 degree = 60 minutes; 1 minute = 60 seconds
**Note: This is not in reference to time!
Deg:min:sec : 30:15:45N, 54:20:10W

22. Three ways to show coordinates continued:
30:15:45N, 54:20:10W =
Decimals: ,
** (south and west are negative numbers)
Found by dividing minutes/60
i.e. 15 minutes = 15/60 = .25
And then seconds/3600
i.e. 45 seconds = 45/3600 = .0125
Add the two together:
= .2625

23. Latitude and Longitude
Together, any point on Earth can be plotted on a map
Use both coordinates together:
Latitude, longitude
40° N, 85° E 10° S, 15° W
Walton: 33:59: N, 84:26: W
This is the Front Office

24. Why Degrees, Minutes, Seconds?
A circle is 360°
When computing various angles, we base our measurements on degrees.
i.e. Right angles are 90 °
An angle between 90° and 91° require requires minutes and seconds to find the specific angle.
In 3D, we add the Z Axis,
which requires the second degree measurement