Unit 1 The Study of Geography

Part 4Earth

• EarthBTW - Earth is moving at 67,000 mph around the sun (Nicolaus Copernicus 1473 - 1543 AD).- Earth is spinning (rotating) 1,037 mph at the equator & 0 mph at the poles. - Thank you gravity!!!! (natural force that pulls everything down to the ground) and Sir Isaac Newton 1642 – 1727 AD.

A sphere is a round geometrical object in 3-dimentional space.

Please write down

When was Earth discovered to be round (sphere)?

• The ancient Greeks knew that Earth was round (sphere) about 2,000 years before Columbus.

- Aristotle 384 - 322 BC

Parthenon in Athens, Greece

- Pythagoras c. 570 - c. 495 BC

Pythagoras – “All celestial bodies are spherical”Aristotle – “Only a sphere can cast a shadow in every direction.” (referencing an eclipse)

• Father of Geography - Eratosthenes (Greek c. 276 – c. 195 BC)

Eratosthenes was the first person to calculate (with incredible accuracy) the circumference of earth, at 25,000 miles, by measuring angles of shadows. Actually, earth is 24,901 miles at the equator & 24,859 through the poles (centrifugal force).

Eratosthenes was only off by 99 miles (equator). obelisk

Alexandria and Syene are both in Egypt.

Eratosthenes wannabe

A Greek named Posidonius, who lived 100 years after Eratosthenes, measured earth at 18,000 miles. Columbus, in 1492 AD, used Posidonius instead of Eratosthenes measurement (Columbus did know that Earth was round before his famous voyage). As a result, he thought that he would get to “India” much faster than he did.

• Location 1. Absolute Location - exact location of a

place on Earth (address). a. Latitude and Longitude- Imaginary lines marking

positions on earth.

Eratosthenes was, also, the first to use the word “geography” and he invented the concept of latitude and longitude. At an old age, Eratosthenes became blind and he died of self-induced starvation.

Eratosthenes

some dude

The ancient Babylonians, actually, assigned numbers to a circle. Ptolemy, however, incorporated them into the longitude and latitude coordinates.

Ptolemy (Greek & Roman citizen who lived in Egypt c. 90 AD – c. 168 AD) – he assigned coordinates to all of the places and geographic features he knew . . . in a grid.

1. Latitude (flatitude) a. Equator - 0 degrees latitude.

b. Tropic of Cancer (North) and

Capricorn (South) - 23.5 degrees

The Seasons: Revolution of Earth around the Sun and the tilt of Earth’s axis (revolution and rotation).

http://www.youtube.com/watch?v=NydSuHoQZqk&feature=related&safety_mode=true&persist_safety_mode=1&safe=active

Eratosthenes was,also, the first to accurately calculate the tilt of Earth’s axis at 23.5 degrees.

Where is the Arctic Circle?

c. Arctic (North) and Antarctic Circles (South) - 66.5 degrees

Equator 0

Tropic of Capricorn 23.5 S

Tropic of Cancer 23.5 N

Arctic Circle 66.5 N

Antarctic Circle 66.5 S

Hemispheres?How to remember:Latitude = Flatitude

2. Longitude a. Prime Meridian - 0 degrees longitude.

Old Royal Observatory in Greenwich, England (U.K.)

http://www.youtube.com/watch?v=-0c1idtn3e8&safety_mode=true&persist_safety_mode=1

http://www.youtube.com/watch?v=cKT16DjHo_8&safety_mode=true&persist_safety_mode=1

http://www.youtube.com/watch?v=YGdw2743vKc&safety_mode=true&persist_safety_mode=1

http://www.youtube.com/watch?v=_JtnNQ6NQhc&safety_mode=true&persist_safety_mode=1

All the lines of longitude meet at the north and south poles.

• Grid System – straight lines that intersect.

• Hemisphere- “half sphere”

1. Northern and Southern2. Eastern & Western

NW NE

SW SE

Earths quadrants

Prime Meridian

Equator0 degrees

0 degrees

NW

SW

NE

SE

• Latitude – N & S• Longitude – E & W

2. Relative Locationa. Where a place is located in relation to other places.

1. Example: NYC is east of Chicago, Illinois.

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• Time on Earth1. Standard Time (since 1884)

a. Based on the Prime Meridian.1. Greenwich Mean Time (GMT)

• Time Zone– one of the 24 regions or divisions of Earth’s surface used to

determine local time in a given locality. Why do we have them?

• Because the sun’s rays are hitting Earth at different times and in different places.

How many time zones are there worldwide?

1. 24 time zones worldwide a. One time zone = about 15 degrees longitude.

1. U.S. Time Zonesa. East to west - Eastern, Central, Mountain, Pacific, Alaska and

Hawaii

China – one time zone

Russia – eleven time zones

The difference between each line of longitude is15 degrees. There are 24 increments of 15 degrees of longitude. How many hours in a day?

http://24timezones.com/

http://www.youtube.com/watch?v=kDWHM00sZJc&safety_mode=true&persist_safety_mode=1

http://www.youtube.com/watch?v=UH3ITIMk2uk&feature=fvwrel&safety_mode=true&persist_safety_mode=1

Hoover Dam

Lake Mead

Lake Mead is right on the border between Arizona and Nevada. The two states are in different time zones (at least for part of the year).

• East (add time) -- West (subtract time)

• Daylight Savings Time- “Spring Forward” and “Fall Back”- There are two states with no daylight savings . . . What are they?

- November 2nd 2014- March 8th 2015

- States with no daylight savings

- Hawaii and Arizona

Hawaii Arizona

• International Dateline1. Marks the place where each day officially begins.2. The west side of the line is always one day ahead of the east side.

http://www.youtube.com/watch?v=Ra4nHwdTQ4Y&safety_mode=true&persist_safety_mode=1

http://www.youtube.com/watch?v=qlmpIuaOBNY&NR=1&safety_mode=true&persist_safety_mode=1

http://www.youtube.com/watch?v=1jbZoTlnmEA&feature=related&safety_mode=true&persist_safety_mode=1

Add Subtract

http://www.youtube.com/watch?v=hPpWCTHjzQI

Learning Objectives

• I can create and analyze maps and graphs to understand the world in spatial terms.

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