1. 2.1 Latitude and Longitude
Mapping our world
2.1 Latitude and Longitude

2. Cartography- science of map making
Uses imaginary gridlines to locate exact points on Earth
The Equator separates the N and S hemispheres
The Prime Meridian separates the W and E hemispheres

3. Latitude Run parallel to the Equator The Equator is 0o latitude
The poles are located at 90o N and 90o S

4. Longitude Semicircles that extend pole to pole
The Prime Meridian is 0o longitude
Points west are numbered 0o-180o W
Points east are numbered 0o-180o E

5. Time Zones There are 24 time zones on Earth Approx. 15o wide
Some time zone boundaries may be shifted in order to make it more convenient locally

6. U.S Time Zones

7. Calendar Dates
The International Date Line is located at the 180o meridian
Traveling west across the International Date Line, you would move into tomorrow
Traveling east across the International Date Line, you would move into yesterday

8. Mapping our world
2.2 Types of Maps

9. Maps- flat projections of a 3D Earth
Mercator Projection
Parallel lines of latitude and longitude
Landmasses near poles are exaggerated

10. Conic Projection Projects points and lines from a globe onto a cone
Distorts at top and bottom
Very accurate for small maps
Used for making road and weather maps

11. Gnomonic Projection Makes Great Circles Distort land and distance
Shortest distance between two points
Useful for plotting long distance air and sea travel

12. Topographic Maps Detailed maps showing hills and valleys
Show changes in elevation
Mountains
Rivers
Forests
Etc…

13. Topographic Maps Contour Lines Contour Intervals
Connect points of equal elevation
Never cross
Contour Intervals
Steeper terrain will have closer lines or larger intervals
See Index Contours

14. Depression Contour Lines
Distinguish areas of lower elevation than the surrounding terrain
Volcanic craters
Mines
Sinkholes

15. Map Legends and Scales Map Legends Map Scales
Explanation of symbols found on a map
Map Scales
Ratio between the distances on a map and actual distances on the surface of the Earth
May be graphic or verbal

16. Mapping our world
2.3 Remote Sensing

17. Remote Sensing
The process of collecting data about Earth from far above Earth’s surface

18. Electromagnetic Spectrum
Satellites detect different wavelengths of energy reflected or emitted from Earth’s surface
Visible light, gamma rays, X rays, UV rays, infrared rays, radio waves, and microwaves

19. Landsat Satellites
Use visible light and infrared radiation to map Earth’s surface
This picture shows how the Texas coast was scarred by Hurricane Ike

20. Global Positioning System (GPS)
Radio-navigation system of at least 24 satellites
Allows users to determine exact position on Earth

22. Sea Beam Relies on sonar to map ocean floor
Uses sound waves to detect and measure objects under water
Sound waves are sent out and a receiving device picks up the echo and calculates the distance