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EndlessYouTube : Repeat/Loop/Replay YouTube. What is a map projection?. A way of showing the curved surface of the earth on a flat map. Homolosine Projection. Robinson Projection. Gall-Peters Map. Planar Projection. Conic Projection. Cylinder Projection.
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What is a map projection? A way of showing the curved surface of the earth on a flat map.
Why are there so many different types of maps? Each map has strengths and weaknesses.
What causes each map’s strengths and weaknesses? One cannot take a 3 dimensional object and make it 2 dimensional without Distortion
Planar/Azimuthal • A planar projection is also called an azimuhtal projection. It distorts size and shape. • Azimuthal projection shows the earth centered in such a way that a straight line coming from the center to any other point represents the shortest distance. • These are often used in air navigation.
Conical • A conic projection comes from the idea of placing a cone over part of the globe. • This projection shows shape fairly accurately, but it distorts landmasses at the edges of the map.
Mercator/Cylindrical • A mercator projection comes from the idea of wrapping a piece of paper around a globe to make a cylinder. Such a map shows shapes fairly accurately but not size or distance. • Areas away from the equator are distorted. Greenland and Alaska will appear much larger than they are on a globe. • These are primarily used for sea travel.
Robinson • A Robinson projection is commonly used in textbooks. It shows the entire earth with nearly the true sizes and shapes of the continents and oceans. • The shapes of the landforms near the poles appear flat.
Gall-Peters • On the Gall-Peters projection, the sizes of landmasses are accurate. In particular South America, Africa and Southeast Asia are shown in their correct size relationship to North America and Europe. • Their shapes, however, are greatly distorted and distances are inaccurate.
The important thing to remember……. • All maps have strengths and weaknesses. • All Have Distortion!!
Heavyweight Champion Robinsonvs. Contender Gall-Peters http://www.youtube.com/watch?v=n8zBC2dvERM