Lesson Latitude

Latitude and Longitude

Makes the World Go Round

​Latitude

Lines of latitude, also called parallels, serve three basic purposes on maps and globes:

a)They are necessary, along with lines of longitude, to determine the position of places.

b)They provide data relative to climate.

c)They can be used to determine distances.

Lines of latitude are imaginary lines that extend west to east across the globe or map. ​

Multiple Choice

Lines of Latitude are called....

• Parallels 

• Meridians

• Sticks

• Markers

equator​

The equator lies midway between the north and the south poles. 

The equator divides the earth into two equal parts, the Northern Hemisphere and the Southern Hemisphere.​

Multiple Choice

True or False: 

The equator splits the world into East and West

• True

• False

​Degree

All circles, including lines of latitude which are circles, may be divided into 360 equal parts or units. Each part is called a degree. The symbol for degree is °, as in 50°. 

Lines of latitude are generally numbered in increments of ten degrees, starting at the equator.

Occasionally other divisions are used:

The tropics of Cancer (23 1/2° N), and Capricorn (23 1/2° S), 

The Arctic Circle (66 1/2° N), and 

The Antarctic Circle (66 1/2° S) ​

Fill in the Blanks

Name ONE of the Tropics

longitude​

Lines of longitude, also called meridians, serve three basic purposes on maps and globes:

a)In conjunction with lines of latitude, they help determine the location of places.

b)They are helpful in measuring time and determining time zones.

c)They can be used to measure distances.

Lines of longitude are imaginary lines that extend from the North Pole to the South Pole. 

Lines of longitude, unlike lines of latitude, are not parallel.​

​Prime meridian

All measurements of longitude start with the prime meridian, which is 0 degrees. 

Longitude is measured in increments of fifteen degrees starting with the prime meridian. 

The enumeration continues for 180 degrees to the east and 180 degrees to the west of the prime meridian. 

The prime meridian and its counterpart on the other side of the world (the 180 degree line) divide the world into two equal parts- the Eastern Hemisphere and the Western Hemisphere.​

Multiple Choice

The Prime Meridian splits the world into 

• East and West

• North and South

• Hot and Cold

• Mountains and Valleys

​Finding distances

Latitude and longitude offer a way to quickly estimate direct east-west or north-south distances. 

For example, there are about 12 degrees of latitude between New Orleans and Chicago. 

This translates into 840 miles. You can calculate this answer quickly because a degree of latitude is equal to about 70 miles. (12 x 70=840)

The distance around the world on the equator is approximately 25,000 miles.​

equator​

​Since the equator is a circle, it contains 360 degrees, as do all circles.

Each degree of longitude on the equator is about 70 miles. 

This is calculated by:

The circumference of the equator in miles is divided by the total number of degrees; thus 25,000 ÷360=70. (The answer is rounded off.)

Since each degree of longitude on the 10°S line is about 69 miles, an airplane flying from point A (10°E) to Point B (40°E) flies 30 degrees, or 2,070 miles.

The parallels of latitude become shorter in circumference as they approach the north and south poles.

​Telling time

​The earth rotates in a west to east direction toward the sun. This is why the sun appears to rise in the east and sets in the west. 

This is why people at a given place on the earth experience dawn, then noon, then dusk, then night. 

The cycle begins again every 24 hours. 

The fact that the earth turns towards the sun is basic to an understanding of how time is figured out on earth. 

​Telling time…

The earth has a circumference of 360 degrees.

Since the earth makes one complete turn in 24 hours, we know that the earth turns 15° every hour. (360 ÷ 25 = 15). 

This is why most maps show longitude lines every 15 degrees. Each 15 degrees stands for the passage of one hour of time.

The abbreviation A.M. is from the Latin phrase ante meridiem, which translates to “before noon”.

P.M. is the latin for post meridiem or “afternday.oon”.

Example: 10pm means ten hours past noon, or 10 hours past the middle of the day​

Open Ended

Look back through your notes:

You were in a plane crash and survive with an old GPS and a Compass

How could knowing your Latitude and Longitude help you know where you are and the environment around you?