Mercator Projections Show Direction but Distort Size Gerardus Mercator designed his map projection in 1569. It shows directions between places accurately near the equator. But it distorts the size of continents, especially near the North and South poles. This is called area distortion.
Lambert Projections Show Polar Areas that Other Maps Distort A Lambert projection is a circular map. It shows size accurately at its center, but not distance or shape. It is good for showing the areas around the North or South pole. Most other map projections distort the shape and size of the Arctic and Antarctica.
In this chapter, you have learned how geographers show information on maps. A map’s title, legend, and symbols can help you understand what a map shows.
You learned how geographers describe where a place is in terms of its absolute location. The global grid allows mapmakers to indicate the exact location of any place on Earth using lines of latitude and longitude. Map scales are useful for describing the relative location of two places. Using a scale, you can estimate about how far two places are from each other.
All Flat Maps Have Distortion Geographers use maps to show features of Earth, such as oceans and continents. But every flat map involves some distortion. The size or shape of landmasses may be distorted. The distances between places may not be accurately shown.
To deal with distortions, mapmakers use different map projections. Many projections are named after the mapmakers who designed them. For example, Arthur Robinson designed the Robinson projection. The world map in section 6 is a Robinson projection. It is a popular projection because it balances the distortions of size and shape. In this way it gives a fairly accurate picture of the world.
You can see several map projections on this page. Note how each projection does some things better than others. As you look at them, think about what type of information each map projection might show best.
Eckert IV Projections Show Size but Distort Shape The Eckert IV projection is an equal-area map. Equal-area maps show the sizes of places accurately. However, they distort shape near the poles. This is called shape distortion. Geographers often use Eckert IV projections to show the number of people in different areas.
Goode’s Homolosine Projections Show Continents but Distort Oceans Goode’s Homolosine projection uses a trick to help us see how the continents compare in size. It snips bits out of the oceans. This trick allows the continents to stretch without distorting their shapes. But it distorts the shape and size of the oceans.