APPENDIX A: MAPS APHUG | BHS | Ms. Justice

Maps  Any map is an incomplete representation of reality: 1. It is smaller than the world it represents 2. It must depict a curved surface on a flat plane 3. It contains symbols to convey information that must be transmitted to the reader  These are three fundamental properties of all maps: 1. Scale 2. Projection 3. Symbols

Map Scale  The scale of a map reveals how much the real world has been reduced to fit on the page or screen on which it appears  The ratio between actual distance and the length given to that distance on the map that can be represented:  Ratio (1:10,000)  Fraction (1/10,000)  Graphic form

Map Scale  "Large scale" refers to maps on which objects are relatively large, "small scale" to maps on which objects are relatively small.

Map Projections: Latitude & Longitude  Lines of latitude and longitude provide a frame of reference for cartographers Prime Meridian, Greenwich, England

Map Projections: Mercator Projection  Invented in 1859 by a Flemish cartographer  Cylindrical projection  Parallels and meridians cross at right angles  Direction is true everywhere on this map – excellent for navigation  Distortion grows toward the poles – continents appear stretched out and misshapen in higher latitudes

Map Projections: Mercator Projection

Map Projections: Robinson Projection  Developed by American cartographer Arthur Robinson in 1963  Lines of longitude curve toward each other in polar regions  Substantially reduces the exaggerated size of polar land masses (better approximates shape)  Lacks the directional utility of the Mercator projections  Used by the National Geographic Society since 1988

Map Projections: Robinson Projection

Map Projections: Interrupted Projection  Broken meridians  Typically, breaks are designed to fall upon less important areas, like oceans  Equal-area map that avoids distortions or land masses

Map Projections: Interrupted Projection

Symbols on Maps: Examples  Prominent dots = cities  Large dot w/a circle around it, or a star = capital  Red lines = roads  Double lines = 4 lane highways  Black lines = railroads  Blue = water  Green = forests  Etc.

Symbols on Maps: Dot Map  A dot map shows a spatial representation  On this map, each dot represents the location of a commercial cell phone tower in the U. S.

 Lines represent a certain consistent height above sea level Symbols on Maps: Contour Map

Other Maps: Thematic Maps

Other Maps: Flow-Line Maps  Good for determining movement – such as migration

Other Maps: Choropleth Maps  Put data into a spatial format.  Useful for determining demographic data, by assigning colors or patterns to areas

Other Maps: Cartograms  Chart and assign data by size World population World child mortality