Page 1 Topic 2 Measuring Earth Set up your Note Packet

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

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 No Page

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. No Page

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. Page 2

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.

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

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

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

Please answer the questions on Page 3 of your Notes

1. 4500°C, 1.2 million atmospheres (+/- 0.2) Answers: 1. 4500°C, 1.2 million atmospheres (+/- 0.2) 2. oxygen 3. -90°C 4. 0°C 5. 12 km

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 No Page

What evidence do we have of Earth’s shape? Earth casts a round shadow during lunar eclipse Video Lunar Eclipse No Page

What evidence do we have of Earth’s shape? Movement of the stars and no movement of Polaris No Page

What evidence do we have of Earth’s shape? Tops of distant objects appear first (ships on the horizon) No Page

What evidence do we have of Earth’s shape? Photos from space from satellites and space probes No Page

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

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. No Page

Earth is not perfectly spherical, the difference is so small that it appears to be perfectly round from all angles. No Page

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????

Eratosthenes

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. No Page

Earth vs. Jupiter No Page

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. No Page

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 No Page

Where would you weigh more?? Less?? At the poles At the Equator No Page

Measuring Earth Notes Page 4 Latitude & Longitude Measuring Earth Notes Page 4

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.

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.

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. _______________ _____

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

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 °

LONGITUDE DETERMINES YOUR TIME

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 Page 5

Page 6 Let’s Look at This Question: How is latitude measured?

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

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

Page 6 Latitude is measured and from the North South Equator

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

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

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

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

Page 6 Let’s do some plotting.

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

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 Page 6 65°N, 50°W 70°S, 15°E 10°S, 135°W

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

Page 7 Location Latitude Longitude 1 30°N 120°W 2 45°S 75°E 3 0° 135°W 6 180° 7 42°N 76°W 8 68°N 9 15°S 15°E 10 22°S 46°W Page 7

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 Page 7