Where in The United States
Are You?
Learning About Latitude & Longitude
Brenda Davis
June 2008
Where Are We?
When we give someone directions
to our home, we use our street
address. Streets are laid out in a
grid and we can use maps to
navigate that grid.
Finding Our Way on Earth
How do we find places without
street addresses? Mapmakers
developed a grid of imaginary lines
to help us locate places on the
Earth.
Lines
• Longitude lines run north and south.
• Latitude lines run east and west.
• The lines measure distances in degrees.
Latitude
Longitude
The Equator
• The equator is 0 degrees latitude.
• It is an imaginary belt that circles the
Earth halfway between the North Pole
and the South Pole.
Equator
Lines of Latitude
Lines of latitude are
also called parallels
because they are always
the same distance
apart. They are
measured in degrees
north or south of the
equator. The North Pole
is at 90 degrees north
and the South Pole is at
90 degrees south.
Prime Meridian
• The Prime Meridian is 0 degrees
longitude. This imaginary line runs
through the United Kingdom,
France, Spain, Africa and Antarctica.
• We measure longitude in degrees
west and east of the Prime
Meridian.
• North America is west of the Prime
Meridian.
• Lines of longitude are not parallel.
They meet at the poles.
Hemispheres
• We use the equator and prime
meridian to divide the world into
four hemispheres, north, south,
east, and west.
• Determining the hemisphere is
the first step in finding a location
on a map.
Quadrants
The hemispheres
allow us to further
divide the Earth into
quadrants.
The NE quadrant - all
latitudes are NORTH and all longitudes are EAST.
The SE quadrant - all
latitudes are SOUTH and all longitudes are EAST.
The SW quadrant - all
latitudes are SOUTH and all longitudes are WEST.
The NW quadrant - all
latitudes are NORTH and all longitudes are WEST.
Making the Grid
When we place the lines of latitude and
longitude together on a map of the Earth, it
forms a grid that we can use to pinpoint any
location on Earth. This is done by determining
which lines of latitude and longitude cross at
that location.
Putting It All Together
• To find a location using latitude and
longitude, you must first determine
whether the location is north or south of
the equator and west or east of the
prime meridian.
• The United States is north of the equator
and west of the prime meridian.
• Humble, Texas is 29.9 degrees north and
95.3 degrees west.
Show What You Know!
Complete the Where In the World Are We? sheet.
Use the map below to help you.
Sources
http://www.epodunk.com/cgi-bin/genInfo.php?locIndex=26577
http://www.owenshistory.info/Powerpoints/Maps/Latitude_and_Longitud
e.pdf
http://yourhistorysite.com/Geography%20Web%20Quest/index_files/Page
1228.htm
http://www.geography.pppst.com/mapskills.html