Latitude and longitude form a global address system that helps people locate any place on Earth. Lines of latitude run east and west, while lines of longitude run north and south from pole to pole. Together, these lines create a grid that can identify a city, mountain, ship, or point in the ocean.
This system matters for maps, navigation, weather tracking, travel, and emergency response.
Latitude is measured in degrees north or south of the Equator, which is 0° latitude. Longitude is measured in degrees east or west of the Prime Meridian, which is 0° longitude and passes through Greenwich, England. A coordinate pair is usually written as latitude first, then longitude, such as 40° N, 74° W.
By reading both numbers and directions carefully, you can find the exact global position of a place.
Key Facts
- Latitude measures distance north or south of the Equator in degrees.
- Longitude measures distance east or west of the Prime Meridian in degrees.
- The Equator is 0° latitude and divides Earth into the Northern and Southern Hemispheres.
- The Prime Meridian is 0° longitude and helps divide Earth into the Eastern and Western Hemispheres.
- Coordinates are written as latitude, longitude, for example 34° N, 118° W.
- Latitude ranges from 0° to 90° N or S, and longitude ranges from 0° to 180° E or W.
Vocabulary
- Latitude
- Latitude is the distance in degrees north or south of the Equator.
- Longitude
- Longitude is the distance in degrees east or west of the Prime Meridian.
- Equator
- The Equator is the 0° latitude line that circles Earth halfway between the North Pole and South Pole.
- Prime Meridian
- The Prime Meridian is the 0° longitude line that runs from pole to pole through Greenwich, England.
- Hemisphere
- A hemisphere is one half of Earth, such as the Northern, Southern, Eastern, or Western Hemisphere.
Common Mistakes to Avoid
- Writing longitude before latitude is wrong because standard coordinates usually list latitude first, then longitude.
- Forgetting N, S, E, or W is wrong because the same degree number can refer to different places depending on direction.
- Calling latitude lines vertical is wrong because latitude lines run east and west around Earth, even though they measure north and south position.
- Thinking the Equator and Prime Meridian are the same type of line is wrong because the Equator is a latitude line, while the Prime Meridian is a longitude line.
Practice Questions
- 1 A location is at 20° S, 45° E. Is it north or south of the Equator, and is it east or west of the Prime Meridian?
- 2 City A is at 10° N, 30° W and City B is at 10° N, 60° W. How many degrees of longitude apart are the two cities?
- 3 Explain why both latitude and longitude are needed to identify an exact location on Earth.