UNIT V: EARTH’S COORDINATE SYSTEMS

How do we describe our position on Earth?

The Earth is broken up using a coordinate system that we can use to pinpoint our location

This system uses latitude and longitude

Latitude

Lines of latitude run laterally, or from side to side, on the Earth

Lines of latitude describe a location North or South of the Equator

Lines of Latitude

Run from 0o at the Equator to 90o North or 90o South

Lines of latitude describe a location North or South of the Equator

How were lines of latitude developed?

Lines of latitude are equal to the angle from the center of the Earth

The Equator is equal to 0o as it is straight out from the center of Earth

Degrees of Latitude

Each degree of latitude is divided into 60 minutes, each minute, 60 second

For example, 44o 32’ 5” N

Latitude and the North Star (Polaris)

The altitude, or angle to, Polaris is equal to the observer’s latitude

This is true only in the Northern Hemisphere because that is where Polaris is visible

Finding Polaris

Polaris is a part of the Little Dipper

Old-Fashioned GPS

The astrolabe allowed explorers to check their latitude traveling across the Atlantic

NYS Latitude and Longitude

Can be found on this reference table

Longitude

Lines of longitude run vertically on our globe and converge at the North and South Poles

Coordinates are written (Latitude, Longitude) Example: (43o N, 77o W)

Prime Meridian

The creation of longitude is very similar to that of latitude. It measures the degrees outward away from the center of the Earth up to 180o West and 180o East. 0o is located at the Prime Meridian

Lines of longitude are often referred to as meridians

International Dateline

Both 180o W and 180o E meet along the International Date Line, a location where a new day begins and an old day ends

Time Zones

Each hour, 15o of longitude is rotated eastward

This becomes a basis for our time zones, each approximately 15o wide

NYS Latitude and Longitude

Can be found on this reference table