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Map Projections. Methods of presenting the curved surface of the Earth on a flat map. Are all Maps created equally? . Distortion results from trying to make a spherical object flat. Mercator Projection. Meridians are stretched apart and parallel to each other instead of meeting at the poles.
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Map Projections Methods of presenting the curved surface of the Earth on a flat map
Are all Maps created equally? • Distortion results from trying to make a spherical object flat.
Mercator Projection • Meridians are stretched apart and parallel to each other instead of meeting at the poles. Where is this map most distorted?
Conic Projection • The top of the map is portrayed accurately, but greater distortion of sizes and distances occurs further from the top. • Latitudes are accurate, so these are used for aeronautical charts.
Flat Plane/Azumithal Projection • Distances measured from the center are accurate, so this is used by pilots and navigators to find the shortest distance between two points. What is distorted?
Equal Area Map Projection • Areas of all land masses are kept proportional, giving the correct perspective of size. What is distorted? Where is it most distorted?
Gall-Peters Projection • Sizes of landmasses are kept in proportion relative to the other landmasses. • Most socially-sensitive projection? What are the disadvantages of this projection?
Robinson Projection • Projection that seeks to create a compromise between size, shape, and distance distortions. • All variables are shown fairly accurately, but not finely enough to be useful in navigation. Because of this, it is only really seen in textbooks and classrooms.
Why the multiple types of projection? • Each has advantages and disadvantages. • Cartographers face many challenges in making maps accurate in terms of sizes, distances, or shapes. Why is this so hard?