Latitude and LongitudeLatitude and Longitude

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IntroIntro Introductory videoIntroductory video http://videos.http://videos.howstuffworkshowstuffworks.com/hsw/8604-geography-basics-.com/hsw/8604-geography-basics-lines-of-longitude-video.lines-of-longitude-video.htmhtm

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Using Latitude and LongitudeUsing Latitude and Longitude

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Location on the Location on the EarthEarth

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The earth is effectively a sphere, so how do we describe where a point is on its surface?

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?What is latitude?

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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.

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?What is longitude? Lines of longitude, called meridians, Lines of longitude, called meridians,

run perpendicular to lines of latitude, run perpendicular to lines of latitude, and all pass through both poles.and all pass through both poles.

longitude values are indicate the longitude values are indicate the angular distance between the Prime angular distance between the Prime Meridian and points east or west of it Meridian and points east or west of it on the surface of the Earthon the surface of the Earth

The Earth is divided equally into 360 The Earth is divided equally into 360 degrees of longitude. There are 180 degrees of longitude. There are 180 degrees of longitude to the east of the degrees of longitude to the east of the Prime Meridian; when the directional Prime Meridian; when the directional designator is omitted these longitudes designator is omitted these longitudes are given positive values. There are are given positive values. There are also 180 degrees of longitude to the also 180 degrees of longitude to the west of the Prime Meridian. Therefore west of the Prime Meridian. Therefore lines of longitude are read in degrees of lines of longitude are read in degrees of either west or easteither west or east

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How precise can we be with How precise can we be with latitude and longitude?latitude and longitude?

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Steps to Find a LocationSteps to Find a Location

1)1) Begin at the point where the Begin at the point where the prime meridian and equator prime meridian and equator intersectintersect

2)2) Move north (up) or south (down) Move north (up) or south (down) the indicated number of degreesthe indicated number of degrees

3)3) From that point while still on From that point while still on the prime meridian, move west the prime meridian, move west (left) or east (right) the (left) or east (right) the correct number of degreescorrect number of degrees

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The EquatorThe EquatorThe line which encircles the Earthat an Equal distance from theNorth and South Poles.

The equator is located at zerodegrees latitude. The equator runsthrough Indonesia, Ecuador,northern Brazil, the DemocraticRepublic of the Congo, and Kenya,among other countries. It is24,901.55 miles (40,075.16kilometers) long. The equatordivides the planet into the Northernand Southern Hemispheres.

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Prime MeridianPrime Meridian The Prime Meridian is The Prime Meridian is

thethe meridian (line of meridian (line of longitude) longitude) at which at which longitude is defined to longitude is defined to be 0°be 0°..

By international By international convention, the modern convention, the modern Prime Meridian is one Prime Meridian is one passing throughpassing through Greenwich, London, Greenwich, London, United Kingdom.United Kingdom.

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Tropics of Cancer & CapricornTropics 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 that passes through both the equator and a tropic), and northern South Africa

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Circles to RememberCircles to Remember

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 owned by no one but claimed by many, and hence it's political future is in question.

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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.

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