Lesson 5 - Understanding Geographical Measurements

 Definitions of Terms used with Longitude and Latitude Measurements

Longitude is measured in degrees East or West of the Prime Meridian. Lines of constant longitude are called "meridians" and run North and South to circle around the Earth.

Latitude is measured in degrees North or South of the equator. Lines of constant latitude run East and West to circle around the Earth.

The North Pole is the northern most point on a map of the world: known as 90 degrees North latitude.

The South Pole, directly opposite the North Pole, is the southern most point on a map of the world: known as 90 degrees South latitude.

The Equator is the imaginary circle, parallel of latitude at 0 degrees, running East and West.

The Prime Meridian is the imaginary half circle, parallel of longitude at 0 degrees, running North and South.

The International Dateline is the half circle parallel of longitude at 180 degrees: runs North and South.

The Northern Hemisphere is the entire half of the world north of the Equator.

The Southern Hemisphere is the entire half of the world south of the Equator.

The Eastern Hemisphere is the half of the world east of the Prime Meridian.

The Western Hemisphere is the half of the world west of the Prime Meridian.

The Tropic of Cancer is located parallel of latitude at 23° 27' north of the equator.

The Tropic of Capricorn is located parallel of latitude at 23° 27' south of the equator.