Earth's Spheres and Mapping Techniques

1. Warm Up 9/16 • Earth’s major spheres are the ______. • Hydrosphere, atmosphere, geosphere, and biosphere • Which of Earth’s spheres includes the oceans, groundwater, lakes, and glaciers? • The hydrosphere • What theory provides a model to explain how earthquakes and volcanic eruptions occur? • Plate tectonics

2. Representing Earth’s Surface Chapter 1, Section 3

3. Determining Location • Latitude – the distance north or south of the equator, measured in degrees • Longitude – the distance east or west of the prime meridian, measured in degrees • Lines of latitude and longitude form a global grid; allowing us to state the absolute location of any place on Earth • The equator divides Earth in two; each half is called a hemisphere (northern and southern) • The prime meridian and the 180º meridian divide Earth into eastern and western hemispheres

4. Global Grid

5. Locating Places Using the Grid

6. Concept Check • How does the global grid divide Earth? • Into hemispheres

7. Maps and Mapping • No matter what kind of map is made, some portion of the surface will always look either too small, too big, or out of place; mapmakers have, however, found ways to limit the distortion of shape, size, and distance • The Mercator projection is used by many seagoing navigators, as it uses lines of longitude that are parallel, making the map rectangular • The Robinson projection shows most distances, sizes, and shapes accurately, but is distorted around the edges • Conic projections are used to make a map of a smaller area • Gnomonic projections are used by sailors and navigators for short distances

8. Projections

9. Concept Check • What major problem must mapmakers overcome? • Representing round Earth on a flat paper causes distortion in shape, size, and distance

10. Topographic Maps • Topographic Map – a map that represents Earth’s surface in three dimensions; it shows elevation, distance, directions, and slope angles • Topographic maps differ from other maps discussed so far because topographic maps show elevation of Earth’s surface by means of contour lines • Contour Line – line on a topographic map that indicates an elevation; every point along a contour line has the same elevation • Contour Interval – on a topographic map, tells the distance in elevation between adjacent contour lines • A map is drawn to scale, where a certain distance on the map is equal to a certain distance on the surface • A map that shows the type and age of the rocks that are exposed, or crop out, at the surface is called a geologic map

11. Contour Lines

12. Geologic Map

13. Concept Check • How do topographic maps indicate changes in elevation? • Contour lines, lines close together indicate a steeper slope

14. Advanced Technology • Today’s technology provides us with the ability to more precisely analyze Earth’s physical properties • Scientists now use satellites and computers to send and receive data, which are then converted into usable forms such as pictures and numerical summaries • The process of collecting data about Earth from a distance, such as from orbiting satellites, is called remote sensing • We can use this technology in our daily lives too; many newer cars use the Global Positioning System (GPS) to provide maps to different destinations

15. US!!!!

16. Concept Check • What types of advanced technology are used in mapmaking today? • Satellites, computers, GPS, sonar, high-powered telescopes, etc.

17. Assignment • Read Chapter 1 pg 2 – 25 • Chapter 1 Assessment • # 1 – 36 pg. 29 – 30