Latitude and Longitude

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Latitude and Longitude
Intro
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Introductory video
http://videos.howstuffworks.com/hs
w/8604-geography-basics-lines-oflongitude-video.htm
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Using Latitude and Longitude
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Location on the Earth
The earth is effectively a sphere,
so how do we describe where a
point is on its surface?
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The most common way to locate
points on the surface of the Earth
is by standard, geographic
coordinates called latitude and
longitude. These coordinates
values are measured in degrees,
and represent angular distances
calculated from the center of the
Earth.
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What is latitude?
We can imagine the Earth as a sphere, with
an axis around which it spins. The ends of
the axis are the North and South Poles.
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All lines of latitude are parallel to the
Equator, and they are sometimes referred to
as parallels. Parallels are equally spaced.
Latitude lines run east and west around the
globe. The equator is the starting point for
measuring latitude.
There are 90 degrees of latitude going north
from the Equator, and the North Pole is at 90
degrees N. There are 90 degrees to the
south of the Equator, and the South Pole is
at 90 degrees S. Therefore, lines of latitude
are always read in north or south degrees.
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What is longitude?
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QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
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Lines of longitude, called meridians,
run perpendicular to lines of latitude,
and all pass through both poles.
longitude values are indicate the
angular distance between the Prime
Meridian and points east or west of it
on the surface of the Earth
The Earth is divided equally into 360
degrees of longitude. There are 180
degrees of longitude to the east of
the Prime Meridian; when the
directional designator is omitted
these longitudes are given positive
values. There are also 180 degrees of
longitude to the west of the Prime
Meridian. Therefore lines of
longitude are read in degrees of
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either west or east
How precise can we be with
latitude and longitude?
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Steps to Find a Location
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Begin at the point where the prime
meridian and equator intersect
Move north (up) or south (down)
the indicated number of degrees
From that point while still on the
prime meridian, move west (left) or
east (right) the correct number of
degrees
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The Equator
The line which encircles the Earth
at an Equal distance from the
North and South Poles.
The equator is located at zero
degrees latitude. The equator runs
through Indonesia, Ecuador,
northern Brazil, the Democratic
Republic of the Congo, and Kenya,
among other countries. It is
24,901.55 miles (40,075.16
kilometers) long. The equator
divides the planet into the Northern
and Southern Hemispheres.
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Prime Meridian
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The Prime Meridian is
the meridian (line of
longitude) at which
longitude is defined to
be 0°.
By international
convention, the modern
Prime Meridian is one
passing through
Greenwich, London,
United Kingdom.
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Tropics of Cancer & Capricorn
The Tropic of Cancer is located at 23.5°
North of the equator and runs through
Mexico, the Bahamas, Egypt, Saudi Arabia,
India, and southern China
The Tropic of Capricorn lies at 23.5° South of
the equator and runs through Australia, Chile,
southern Brazil (Brazil is the only country
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that passes through both the equator and a
tropic), and northern South Africa
Circles to Remember
The Arctic Circle is also the name given the
region around the North Pole. It includes the
Arctic Ocean, thousands of islands, and the
northern parts of Europe, Asia, and North
America, including the Arctic and Subarctic
regions of Alaska, Canada, Greenland, Iceland,
Scandinavia, Siberia and the Russian Far East.
The Antarctic Circle is the region in the Southern
Hemisphere surrounding the South Pole. The nearest
neighbouring country is Argentina and the second
nearest is New Zealand. The Antarctic Circle is the
coldest and driest place on earth and is owned12by no
one but claimed by many, and hence it's political future
is in question.
Flash Animation
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http://olc.spsd.sk.ca/DE/k9mod/Map
skill/mod3fl5.swf
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