MAP PROJECTIONS TYPES OF MAPS AP HUMAN GEOGRAPHY

MAP PROJECTIONS & TYPES OF MAPS AP HUMAN GEOGRAPHY

MAP PROJECTIONS

MAP PROJECTIONS • Cartographers have to deal with the problem of making maps of a spherical earth onto a flat surface this leads to distortions • Shape can be distorted • Distance between two points can increase or decrease • Relative size may be altered, areas can appear much larger than they really are • Direction can be distorted

ROBINSON PROJECTION

ROBINSON PROJECTION • More accurately shows the area near the poles • Used to show proportions of land to water • Distorts cardinal directions and distance

MERCATOR PROJECTION • Used primarily for navigation since it is easiest to plot direction • Increased distortion the further away from the equator • Makes the North look much larger

GALL-PETERS PROJECTION

GALL-PETERS PROJECTION • Focuses more on land area accuracy • Released in 1974, based off a 1800 design • More accurately shows southern hemisphere as larger than northern hemisphere • Areas near the poles are stretched horizontally

GOODE HOMOLOSINE PROJECTION

DYMAXION PROJECTION

TYPES OF MAPS

MAPS AS A TOOL TO UNDERSTAND SPATIAL PATTERNS • Maps can give insight to how a phenomenon is occurring and provide the starting point for understanding the why Example: A doctor figures out why a group of specific people are getting cholera by using a map to see they were all living in the same general area and using the same water pumps, which were causing the cholera outbreak

CHOROPLETH MAPS • A map showing quantity by area. It uses shades of colors to show intervals

ISOLINE MAPS • A map that is used to display distributions. It consists of lines that connect to show equal value

PROPORTIONAL (GRADUATED) CIRCLE MAPS

DOT MAPS

CAUTION: MAPS CAN BE DECEIVING! • Every map is flawed in some way • Cartographers can be wrong, include inaccurate data, or make you perceive something differently that they want you to see by distorting the map

• Glancing at that map, we’d think California, Texas, Florida, and New York were horribly dangerous places to live • The problem is that we’re basically looking at a map of population. Of course the more people live in a place, the more crimes (all else being equal) will be committed there

• These maps, from ads for Verizon Wireless, show 3 G network coverage by Verizon and AT&T. The impression they give is that most of the US isn’t covered by AT&T at all • BUT if you look at the map of population density, you will see that areas with the most people are covered