1. Mapping Our World
Chapter 2
Earth Science

2. Essential Questions
How does latitude and longitude help give a location’s complete coordinates?
Why ae there different time zones from one geographic area to another?
What are the similarities and differences between different types of maps?
How are gradients on a topographic map calculated?
What are some of the different types of remote sensing that are used to map Earth’s surface and oceans?

3. What are maps? Flat models of 3-D objects
Used for centuries to define borders and find locations
A map is a picture or representation of the Earth's surface, showing how things are related to each other by distance, direction, and size.
A person who creates map as a profession is called a cartographer.

4. Earth’s Hemispheres The earth is divided into halves of equal parts
When divided in the center of Earth horizontally,
the top hemisphere is called the Northern Hemisphere. The USA is located in the Northern Hemisphere.
The bottom of Earths is called the Southern Hemisphere.
When Earth is divided in the middle vertically,
The left side is referred as the Western Hemisphere
The right side is referred to as the Eastern Hemisphere

6. How are maps made?
Cartographers use imaginary grid of parallel lines to locate points on Earth.
Latitude
Longitude
Equator
Prime meridian
Time zones
International Date Line

7. Latitude Lines on a map running parallel to the equator
Distance in degrees north or south of the equator
Equator is 0 degrees
The poles are 90 degrees
Each degree of latitude = 111 Km on Earth’s surface Why?
Earth is a sphere and can be divided in 360 degrees
The circumference of Earth is 40,000 km.
Divide 40,000 by 360 = ?

8. Longitude
Used to locate positions in east and west directions called meridians
Distance in degrees east or west of the prime meridian
Prime meridian is located in Greenwich, England, home of the Royal Navy Observatory
Points west of the prime meridian are numbered from 0 degrees to 180 degrees west
Lines are not parallel. Why?
Where east meets west, it is called the International Date Line.

9. Time Zones Earth is divided into 24 time zones. Why?
Every hour the Earth spins approximately 15 degrees, so each time zone is 15 degrees wide. Pg. 33
Each time you travel through a time zone, you gain or lose time. This is how Felious Fog in the move, “Around the World in 80 Days,” won his wager.

10. Practice Locating Places on Earth Handout
Latitude is written before the longitude
Extra Credit – Mini Lab page 32 (must be turned in before test)

11. Review Questions pg. 33 Complete and Turn In
Why is it important to give both latitude and longitude when giving coordinates?
How does the distance of a degree of longitude vary from the equator to the poles?
Estimate the time difference between your home and places that are 60 degrees east and west longitude of your home
If you were flying directly south from the north pole and reached 70 degrees north, how many degrees of latitude would be between you and the south pole?

12. Types of Maps
Mercator projections – map with parallel lines of latitude and longitude
Land mass sizes get distorted pg. 34
Conic projection – pints and lines on a globe are projected onto cone-shaped paper
Used for road maps and weather maps
Very accurate despite some distortion at the top of the map pg.35
Gnomonic projection – projected points and lines from a globe onto paper that touches the globe at a singe point
Topographic maps – show changes in elevation on Earth’s surface
Geologic map – shows distribution, arrangement and types of rocks located below the soil
Satellite maps – Landsat, OSTM/Jason-2, SeaBeam, and GPS
Environmental maps - GIS

13. Topographic Maps Contour lines Contour intervals Index contours
Depression contour lines
Relief

14. Topographic maps show a 3 dimensional world in 2 dimensions by using contour lines. Many people have trouble reading these maps, because they have mountains and valleys are represented with concentric circles and lines.
Many hikers use topographic maps, especially in areas where there are no roads with signs. Geologists depend on topographic maps to record the types of rocks. Engineers use topographic maps when they are planning roads, buildings, or other human–made structures. Imagine designing a city without considering where hills and valleys are located

16. Calculating Gradient Gradient refers to the steepness of a slope.
To measure gradient, divide the change in elevation between two points on a map by the distance between the two points.
Practice by completing Problem-Solving Lab on page 37.

17. Practice Complete handouts as a class
Complete Problem Solving lab page pg. 49 (Honors only)
Write a formal lab report
Show all calculations
Use data to support your answers
Build a topographic map

18. Geographic Map

19. Map Features
Map scale – the ratio between distances on a map and actual distances on Earth’s surface
Verbal scales – statement using words (one centimeter is equal to one kilometer)
Graphic scales – consists of a line that represents a certain distance
Fractional scales – expresses distance as a ratio (1:550)
Map legend – explains what the symbols represent

20. Landsat satellites
Remote sensing – gathering data about Earth from instruments mounted on satellites, planes and ships.
Landsat satellites collect energy reading in various wavelengths
Colors are assigned to each wavelength
Used to help in natural disaster relief planning, study pollution, melting glaciers

21. Satellite Imaging Maps
Ocean Surface Topography Mission (OSTM)
Uses radar to measure and map the height of the sea surface
Distance to the water’s surface is calculated using the known speed of light (3.0 x m/s)

22. Bell Work In which hemisphere do we live? Create a map of your room.
Illustrate a topographic map with an elevation of 200 m and 50m contour intervals.
Predict how a geologic map could help a city planner decide where to build a city park.
Determine the gradient of a slope that starts at an elevation of 55m and ends 20 km away at an elevation of 15 m.
Compare the contour intervals of a flat area to a steep hill.
Compare a depression contour to an uphill contour line.