From Globes to MapsFrom Globes to Maps

Globe is a three-dimensional scale model of Earth. Presents the most accurate depiction of geographic information.

Map is a symbolic representation of all or part of the earth on a flat piece of paper. Maps can be useful in showing small areas in

great detail.

From 3-D to 2D

•Cartographers use mathematical formulas to transfer information from a round globe to a flat map.

•To create maps, cartographers project the round earth onto a flat surface – making a map projection.

Basic Categories of Map Projections

Planar – Shows the earth centered in such a way that a strait line coming from the center to any other point represents the shortest distance. It is most accurate at its center (the poles).

Basic Categories of Map Projections

Cylindrical – is based on the projection of the globe onto a cylinder. This projection is most accurate near the equator.

Basic Categories of Map Projections

Conic – Is created by placing a cone over part of the globe. It is best suited for showing limited east-west areas that are not too far from the equator.

Map Map ProjectionsProjections

Winkel Tripel ProjectionWinkel Tripel Projection

Most widely used map in the world. Provides good balance between the size and shape of land areas as they are shown on the map.

Robinson ProjectionRobinson Projection

The continents appear much as they do on the globe however, there is minor distortion near the poles

Goode's Interrupted Equal-Area ProjectionGoode's Interrupted Equal-Area Projection

A map that looks something like a globe that has been cut apart and laid flat. Shows the true size and shape of earth’s landmasses but the distances are somewhat distorted.

Mercator ProjectionMercator Projection

Once the most commonly used projection, increasingly distorts size and distance as it moves away from the equator.