Typical Graph
This is an example of a typical graph we are all familiar with. The graph is made up of different “points” with lines that connect the points.
Typical Graph
Y axis
Each point has two values: The “X” value that runs along the horizontal “X” axis The “Y” value that runs along the vertical “Y” axis
X axis
Typical Graph
X value is always stated first Followed by the Y value The “origin” is the point where the 2 axes intersect with a X value of (0,0)
Y
(3,8)
(9,5)
(0,0)
Typical Graph
A point can also have negative (-) values Negative X values are to the left of the origin (0,0) Negative Y values are below the origin
Y (-X,+Y) (+X,+Y) (0,0)
X
(-X,-Y) (+X,-Y)
East West, North South on The Earth
Let the X axis be the Equator.
Y
Let the Y axis be the Prime Meridian that runs through X Greenwich outside of London.
Lat/Long are the 2 grid points by which you can locate any point on earth.
East West, North South on the Earth N
W
S
Let each of the four quarters then be designated E by North or South and East or West.
East West, North South on the Earth
(N, W)
(N, E)
The N tells us we’re north of the Equator. The S tells us we’re south of the Equator. The E tells us that we’re east of the Prime Meridian. The W tells us that we’re west of the Prime Meridian.
(S, W)
(S, E)
East West, North South on the Earth
(N, W)
Prime Meridian
That means all points in North America will have a North latitude and a West longitude because it is North of the Equator and West of the Prime Meridian.
East West, North South on the Earth
What would be the latitude and longitude directions in Australia?
Prime Meridian
If you said South and East , you’re right!
Latitude is the What is Latitude? distance from the equator along the Y axis.
90°N
Y
All points along the equator have a value of 0 degrees latitude.
X
North pole = 90°N
South pole = 90°S
90°S
Values are expressed in terms of degrees.
What is Latitude?
90°N
Y
X
Each degree of latitude is divided into 60 minutes.
90°S
Each minute is divided into 60 seconds.
This is also true of longitude.
What is Latitude?
90°N
For Example:
Y
37°, 02’,51’’N
X
This is close to the latitude where you live.
90°S
What is Longitude?
Longitude is the distance from the prime meridian along the X axis. All points along the prime meridian have a X value of 0 degrees longitude. The earth is divided into two parts, or hemispheres, of east and west longitude.
Y
180°W
180°E
What is Longitude?
Y
The earth is divided into 360 equal slices (meridians)
X
180 west and 180 east of the prime meridian
180°W
180°E
What is Latitude?
90°N
Y
Our latitude and longitude might be:
X
37°, 03’,13’’N 76°, 29’, 45’’W
90°S
The origin So Where is (0,0)? point (0,0) is where the equator intersects the prime meridian. (0,0) is off the western coast of Africa in the Atlantic Ocean.
See If You Can Tell In Which Quarter These Lon/Lats Are Located
1. 41°N, 21°E
A C
B
2. 37°N, 76°W 3. 72°S, 141°W 5. 15°N, 29°E 6. 34°S, 151°E
D 4. 7°S, 23°W
1. B
2. A 3. C 4. C
5. B
6. D
See if you can find those same latitude/longitude locations on a map!
Positioning on the Earth’s Surface
East is the direction of rotation of the Earth Prime Meridian 0o Longitude North Pole
Latitude: (90oN to 90oS) Longitude: (180oE to 180oW)
Tropic of Cancer
21st June 22nd Sept 20th March
Latitude 23½o North
90 60 30 W 30 60ooEo 9090 66½o o 23½ 900 23½o
Equator
22nd December
Latitude 0o Latitude 23½o South Longitude 90oEast
Tropic of Capricorn Longitude 90o West Longitude 60o West
Longitude 60o East
Longitude 30o East
South Pole Latitude and Longitude together enable the fixing of position on the Earth’s surface.
Longitude 30o West
Now you’re ready to find some locations on a map!