1. Page 1
Topic 2 Measuring Earth
Set up your Note Packet

2. Page 2
Earth’s Sphere’s
Earth outermost regions can be divided into three major areas or spheres. They differ from each other in composition and, very importantly, in density.
 1. Atmosphere:
shell of gases that surround Earth, extends outward several hundred kms-but still very thin
the least dense of Earth’s three spheres

3. The atmosphere is subdivided into layers.
A. Troposphere
Lowest layer of the atmosphere
contains most of the atmosphere’s gases including oxygen and water vapor
weather occurs here
Stratosphere
Layer above the troposphere
ozone layers occurs here
temperature increases with altitude
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4. The atmosphere is subdivided into layers.
Mesosphere
Portion of the atmosphere from about 30 to 80 kilometers
temperatures ranging from about 10 to 90 degrees Celsius as you go up.
Thermosphere
Outermost layer of the atmosphere
Aurora Borealis (Northern Lights) occurs here.
We are not going to spend a lot more time on the atmosphere now because we will study it in much greater detail in another section.
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5. Hydrosphere This is the name for the waters that cover Earth on over 70% of its surface. “Hydro-” = water. Very thin compared to other spheres, averaging 3.5 – 4 km thick. Includes oceans, lakes, rivers, etc.
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6. Lithosphere Page 2 The most solid portion of Earth
the most dense sphere
It extends downward from surface of Earth from 70 – 150 km
Consists of rock and soil under our feet
It is what makes up our mountains, valleys and plains, even the ones under the oceans.

7. Information regarding
Page 3
Earth’s Spheres
Information regarding
Earth’s atmosphere
can be found on page
of the ESRTs 14

8. Information regarding
Page 3
Earth’s Spheres
Information regarding
Earth’s interior
can be found on page
of the ESRTs

9. Information regarding
Page 3
Earth’s Spheres
Information regarding
Earth’s hydrosphere
can be found on page
of the ESRTs 4

10. Please answer
the questions
on Page 3 of
your Notes

11. 1. 4500°C, 1.2 million atmospheres (+/- 0.2)
Answers:
°C, 1.2 million atmospheres (+/- 0.2)
2. oxygen °C
4. 0°C km

12. Earth’s Shape
A History Lesson:
For thousands of years, many people thought Earth was flat. We now know that Earth is round, or to be more precise, a:
sphere
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13. What evidence do we have of Earth’s shape?
Earth casts a round shadow during lunar eclipse
Video Lunar Eclipse
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14. What evidence do we have of Earth’s shape?
Movement of the stars and no movement of Polaris
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15. What evidence do we have of Earth’s shape?
Tops of distant objects appear first (ships on the horizon)
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16. What evidence do we have of Earth’s shape?
Photos from space from satellites and space probes
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17. SHAPE OF EARTH Page 3 Oblate Spheroid Flattened at the poles
1. _____________________________
Bulges at the equator
2. _____________________________
Earth’s equatorial circumference is __________ than its polar circumference.
larger

18. Actually, Earth is not a perfect sphere. Its shape is actually an:
oblate spheroid
Circumference of Earth at the equator is 40,076 km and its diameter is 12,757 km.
Circumference of Earth through the poles is 40,008 km and diameter is 12,714 km.
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19. Earth is not perfectly spherical, the difference is so small that it appears to be perfectly round from all angles.
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20. Eratosthenes
Estimated the circumference of the Earth by conducting a clever experiment in 200 B.C.
Used observations of the Sun
Very accurate, problem,
what is a stadia????

21. Eratosthenes

22. The Reason Why the Earth is wider
at the Equator and shorter at the Poles
Earth rotates (spins) and it rotates at a faster rate at the equator, causing Earth to bulge outward there.
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23. Earth vs. Jupiter
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24. Earth vs. Jupiter It would be more oblate because it rotates
If Jupiter rotates once in about 10 hours. Would Jupiter be more oblate, less oblate, or just as oblate as Earth and why?
It would be more oblate because it rotates
faster than Earth. (10 hours vs 24 hours)
or 2.4 times faster. This would cause the
area of its equator to bulge outward even
more than Earth’s.
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25. Gravitational Measurements prove the Earth is an Oblate Spheroid
The further from the center of the Earth the less you would weigh
The closer to the center of Earth the more you weigh
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26. Where would you weigh more?? Less??
At the poles
At the Equator
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27. Measuring Earth Notes Page 4
Latitude & Longitude
Measuring Earth Notes Page 4

28. Page 4 LATITUDE AND LONGITUDE 1. Equator is 0° latitude line. 2.
Angular distance north or south of the equator 1.
Equator is 0° latitude line. 2.
Latitude lines are parallel. 3.
Maximum latitude is 90°. 4.
In the Northern hemisphere one can determine their latitude by finding the altitude of Polaris.

30. Positioning on the Earth’s Surface
East is the direction of rotation of the Earth
Equator
Latitude 0o
Latitude: (90oN to 90oS)
North Pole
South Pole
Prime Meridian
0o Longitude
Longitude: (180oE to 180oW)
Longitude 60o West
Longitude 30o West
Longitude 60o East
90o
Longitude 30o East
66½o
Latitude 23½o North
Tropic of Cancer
23½o
21st June
22nd December
22nd Sept
20th March
90oW
60oW
30oW
90oE
30oE
60oE
23½o
900
Latitude 23½o South
Tropic of Capricorn
Longitude 90o West
Longitude 90oEast
Latitude and Longitude together enable the fixing of position on the Earth’s surface.

31. Page 4 Important Parallels 1. ____________ ___ 90°N North Pole 90°S
1. ____________ ___
90°N
North Pole
Important Parallels
90°S
2. ______________ ____
South Pole 5. 4. 1. 0°
Equator
3. ______________ ____ 3. 6.
Tropic of Cancer
23.5°N
4. ______________ _____ 7.
66.5°N
Arctic Circle
5. ______________ _____
Tropic of Capricorn
23.5°S
6. _______________ _____ 2.
Antarctic Circle
66.5°S
7. _______________ _____

32. EXPLAIN WHY TWO CIRCLES OF LATITUDE NEVER TOUCH.
Page 4
EXPLAIN WHY TWO CIRCLES OF LATITUDE NEVER TOUCH.
Because they are parallel!

33. Page 5
Measures angular distances east or west of the Prime Meridian.
B. Longitude - 1.
The Prime Meridian is 0° longitude and passes through Greenwich England. 2.
Longitude lines meet at the North and South poles. 3.
Maximum Longitude is 180° East or West. (The International Date Line) 4.
Longitude lines help us determine time of day.
Draw lines of longitude on your diagram and label the Prime Meridian with degrees °

35. LONGITUDE DETERMINES YOUR TIME

36. You are on a boat which is crossing the Prime Meridian
You are on a boat which is crossing the Prime Meridian. The altitude of Polaris is 50°. Explain how you know the boat’s location is 50° North latitude and 0° longitude.
A. Your latitude is always = to the altitude of Polaris
B. The Prime Meridian is 0° longitude
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37. Page 6
Let’s Look at This Question:
How is latitude measured?

38. To get to the next line of latitude, you must move
Page 6
To get to the next line of
latitude, you must move
in which of two directions? 10 20 30 40 50 60 70 80 90 15 45 75
105
120
135
150
165
180 E F G H
Latitude
Equator

39. Page 6 10 20 30 40 50 60 70 80 90 15 45 75
105
120
135
150
165
180 E F G H
North
South

40. Page 6
Latitude is measured
and
from the
North
South
Equator

41. Page 6
Let’s Look at This Question:
How is longitude measured?

42. To get to the next line of longitude, you must move
Page 6
Longitude 10 20 30 40 50 60 70 80 90 15 45 75
105
120
135
150
165
180 E F G H
To get to the next line of
longitude, you must move
in which of two directions?
Prime Meridian

43. Page 6 10 20 30 40 50 60 70 80 90 15 45 75
105
120
135
150
165
180 E F G H
West
East

44. Page 6
Longitude is measured
and
from the
East
West
Prime Meridian

45. Page 6
Let’s do some plotting.

46. On the coordinate system, plot the coordinates given in your notes:10 20 30 40 50 60 70 80 90 15 45 75
105
120
135
150
165
180 E F G H
Page 6 D A B C

47. 20°N, 75°E Page 6 65°N, 50°W 70°S, 15°E 10°S, 135°W
State the coordinates for each of the letters in the figure above: 10 20 30 40 50 60 70 80 90 15 45 75
105
120
135
150
165
180 E F G H
20°N, 75°E
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65°N, 50°W
70°S, 15°E
10°S, 135°W

48. (North, South) latitude and (East, West) longitude.
Page 6
All locations in the
United States have a
(North, South) latitude
and (East, West) longitude.

49. Page 7 Location Latitude Longitude 1 30°N 120°W 2 45°S 75°E 3 0° 135°W6
180° 7
42°N
76°W 8
68°N 9
15°S
15°E 10
22°S
46°W
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50. CONTINENTS OCEANS Page 7 A N. America B S. America C Europe D Asia E
Africa F
Australia G
Antarctica
OCEANS H
Atlantic I
Pacific J
Indian K
Antarctic or Southern L
Arctic
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