The global grid makes it possible to state the “absolute location” of a place – exactly where it is. http://matagalatlante.org/nobre/featpost/doc/featexamples.html http://www.psdgraphics.com/backgrounds/world-globe-background/
Absolute location – longitude & latitude – is like a global address. http://amyrondinel.com/2010/09/home-is-where-the-heart-is/
http://www.hightunnels.org/ForEducators/Planning/FullMoonFarmCaseStudy/planningorientationlatitude.htm Los Angeles, California: 34°N 118W°
Lines of longitude get closer together as they move away from the Equator & to the poles. http://www.mapsfordesign.com/North-Atlantic-Ocean-Global-Projection-PowerPoint-Map.html
http://www.mapsfordesign.com/North-Pole-Global-Projection-PowerPoint-map.htmlhttp://www.mapsfordesign.com/South-Pole-Global-Projection-PowerPoint-Map.html And longitude lines actually all meet at the poles.
Longitude lines tell us how far east or west we are from the Prime Meridian. http://www.ukdivers.net/chartwork/chartintro.htm
Anywhere you are on the 30°E line, you are 30° east of the Prime Meridian. http://www.hammondmap.com/catalog/classroom_activities/latlong1.html
Anywhere you are on the 30°W line, you are 30° west of the Prime Meridian. http://www.hammondmap.com/catalog/classroom_activities/latlong1.html
The Equator is a real location. But who decided where to put the Prime Meridian?
In the 1500s, when the Portuguese controlled the Atlantic, they drew the first Prime Meridian passing through the Madeira Islands. Graphicmaps.com
Portugal owned the Madeira Islands, so they thought it was a good idea to use THEIR land for the Prime Meridian location. We control the Atlantic. So, of course, it makes perfect sense that we would put the Prime Meridian through OUR land. WE are the center of the world! http://www.fotosearch.com/clip-art/spanish.html Graphicmaps.com
This Prime Meridian was used by most mapmakers for the next 300 years. http://www.math.nus.edu.sg/aslaksen/gem-projects/hm/0203-1-10-instruments/glossary.htm
When the British got control of the Atlantic, they set a new Prime Meridian, right through England! Graphicmaps.com
NOW look who’s in charge of the Atlantic! England is now the center of the universe, so we will re-draw the Prime Meridian to go through England! http://colquitt.k12.ga.us/wjwpg2/Explorers/explor.htm
In 1884, 25 countries reached agreement at a conference in Washington D.C. that the location in Greenwich, England, would be the “Prime Meridian” - zero degrees. Over a period of many years, other countries accepted and adopted the decision. http://www.brannelastronomy.com/articles/meridian.htm
http://www.randform.org/blog/?p=1472http://www.flickr.com/photos/31808957@N04/2993256325/ the Prime Meridian Royal Observatory, Greenwich, England