Latitude and Longitude
D.Knauss
RRHS
2009
Coordinates
• The location of any object can be located by
the intersection of two lines.
• The Earth is divided into two sets of lines.
Latitude Lines and Longitude Lines
Longitude Lines
• Longitude Lines run from the North to the
South pole and are equal in length. They tell
you where you are East and West of the
Prime Meridian (runs through Greenwich,
England).
0o longitude
30o East
longitude
30o West
longitude
Longitude Lines
• Looking at the Earth from above the North
Pole, you can see the Prime Meridian and
the International Date Line.
0o Prime Meridian
90o East
90o West
180o International Date Line
International Date Line
• The International Date Line sits on the 180º
line of longitude in the middle of the Pacific
Ocean. It is the imaginary line that separates
two consecutive calendar days.
- It is not a perfectly straight line and has
been moved slightly over the years to
accommodate needs of varied countries in
the Pacific Ocean.
International Date Line
• Immediately to the left of the International
Date Line (the date) is always one day
ahead of the date (or day) immediately to
the right of the International Date Line in
the Western Hemisphere. So, travelling east
across the International Date Line results in
a day, or 24 hours being subtracted.
Travelling west across the International
Date Line results in a day being added.
International Date Line
and the
Prime Meridian
Not a Straight Line!
Latitude Lines
• Latitude lines run from East to West and tell
you where you are North and South of the
Equator.
90o North
latitude
0o latitude (Equator)
90o South
latitude
Degrees, Minutes, and Seconds
• Since the world is so big and there are only
360 degrees in a circle, the thickness of a 1degree line could be the size of Rocky
River!
• Therefore, scientists have broken down the
degree into smaller units which are based on
units of time since the current time zone
values are mostly based on Longitude lines.
Degrees, Minutes, and Seconds
• For every degree, there are 60 minutes
• For every minute, there are 60 seconds
• So, a very general location would look like
this: 150o North and 30o West
• A very detailed location would look like
this:
• 150o 15’ 35.4” North and 30o 25’44.4” West