1. Earth & Space Science Chapter 2 Mapping Our World

2. Mapping the Earth Latitude o Parallel o Equator = 0⁰ o Poles = 90⁰ Longitude o Semicircles, not parallel o Prime meridian = 0⁰ o International Date Line = 180⁰ o 15⁰ = 1 hour

3. Map projections It is difficult to represent the three dimensional Earth on a two dimensional map. All maps have distortions. Different types of maps are used for different purposes. Map projections: – Mercator – Conic – Gnomonic

4. Conic and Gnomonic Projections

5. Mercator projection Able to show most of the earth’s landmasses Distortion increases with distance from equator

6. Distortion of a Mercator Map

7. Peters Map projection

8. Winkel Tripel Map Projection

9. Topographic Maps Hershey kiss map

10. Rules for Contour Lines Contour lines never cross or intersect. When a contour line crosses a river the “V” always points upstream. The slope is steep when the contour lines are close and flat when contour lines are far apart. Contour lines form loops or are lines that go the edge of the map

11. Sinkholes and Craters A depression is shown by contour lines with small “hachures” pointing toward the lowest point.

12. Match profile and contour map A profile is the side view of a land surface between two points on a topographic map representing the shape of the land.

13. Remote Sensing Landsat Satellite: – visible and infrared radiation – Scan Earth’s entire surface in 16 days TOPEX/Poseidon – High frequency radar signals – Ocean floor and sea level mapping from satellite Sea Beam – Sonar (sound waves) ocean floor mapping from a ship

14. GPS and GIS GPS (Global Positioning System): Satellite navigation system Airplanes, ships, cars, phones GIS (Geographic Information System): Layering different types of maps