1. Earth's Dimensions Profiles Topographic Maps Latitude Longitude
Equator
Elevation
Earth
Contour Lines
Prime Meridian
Isoline
Altitude
Slope
Gradient

2. How can we prove the Earth’s shape?
Earth appears spherical from space.
Earth is actually an _______________.
It is slightly "flattened" at the poles, and "bulges" slightly at the equator due to rotation on its axis.
oblate spheroid
How can we prove the Earth’s shape?

3. Photographs from space

4. Earth’s shadow on the moon
Lunar Eclipse
Earth’s shadow on the moon

5. Lunar Eclipse – Note the curved shadow

7. Explorers sailed around the world

8. Ships seem to rise or sink over horizon

9. ___________+___________= POLATITUDE
Polaris
Latitude
In the N. Hemisphere, the altitude of Polaris changes with your latitude

10. Polaris
Polaris clip

11. (weight = mass * force of gravity)
Weight varies slightly from the poles to the equator, because the equator is slightly further from the center of mass than the poles.
(weight = mass * force of gravity)

12. Latitude
East
Lines of latitude run & _ across the Earth, but measure ______& _____.
The reference lines for all lines of latitude is the __________.
The equator is at latitude.
All lines of latitude run_______ to the equator.
West
North
South
equator 0°
parallel

13. Lines of Latitude
Latitude can be determined by finding the altitude of Polaris
Polaris = Latitude
= °N
83° =
= °S
42°
83°N
Can not see the N. Star in the S. Hemi

16. Important Lines of Latitude
a) Equator =
b) Tropic of Cancer =
c) Tropic of Capricorn =
d) Arctic Circle =
e) Antarctic Circle =
f) North Pole =
g) South Pole = 0°
23.5°N
23.5°S
66.5°N
66.5°S
90°N
90°S

17. North Pole 90°N
Arctic Circle 66.5°N
Tropic of Cancer 23.5°N
Equator 0°
Tropic of Capricorn 23.5°S
Antarctic Circle 66.5°N
South Pole 90°S

18. Longitude
Lines of longitude run ________ & _______ across the Earth, but measure ______&_____.
The reference line for all lines of longitude is the _____ ___.
The Prime Meridian is at ______ longitude.
Line of longitude DO NOT run parallel to each other like lines of latitude. Lines of longitude are ______________ to each other by the poles and ____________ from each other by the equator.
North
South
East
West
Meridian
Prime 0° .
closer
farther

19. Longitude
The furthest West you can travel from the Prime Meridian is ________ which is the ___________ ________ _______.
180°
Line
International
Date

27. Time Zones and Longitude
Local Noon is defined
as the time when the sun
is directly overhead of
an observer

28. Time Zones and Longitude
The Earth rotates 360o in a 24 hours period. (a rate of 15o per hour)
Because of the Earth’s rotation, different parts of the Earth are in daylight at different times of the day
This requires humans to set-up some standards in terms of world times

29. Important Longitudes and Time Zones
180o Longitude is the International Date Line, where the day begins.
If you move cross the Int’l Date Line from the east you gain a day
If you move cross the Int’l Date Line from the west you lose a day
0o Longitude is set at Greenwich Mean Time (GMT)

30. Using Longitude to Find Times
Differences of 15o Longitude, relates to a difference of 1 hour of time
Add or subtract hours from local time based upon motions east or west.
- Move East = ______ ________
- Move West =________ _______
add
hours
subtract
hours

31. Time Zones

33. True Time Zones