UNIT 1 LESSON MAPS & PROJECTIONS

THE STUDENT WILL BE ABLE TO…  Discuss the various functions of maps and understand what a projection is.  We’re only glancing at maps today b/c you did so much with them in “True Maps, False Impressions.”

MAPS  Maps are the basic tool that geographers use to describe where things are at.  A map is “a two-dimensional or flat-scale model of Earth’s surface” (Rubenstein, 2014, p. 5).  The science of mapmaking is called “cartography.”  Present day geographers use computers and satellite imagery.  Maps can be used as either a reference tool or as a communication tool.

EARLY MAPS & REFERENCE  Earliest maps were reference tools.  Used for navigation in getting from Point A to Point B  Eratosthenes ( B.C.E): 1 st person to use word Geography and made one of earliest maps.  Ptolemy (C.E ): Made maps that were not remade for about 1,000 years (No one improved on them) Remake of Eratosthenes map in from the 1800’s

MAPS & COMMUNICATION  Maps are still used today for navigation, but we also use them a lot for communication.  The communication aspect really comes into play during a cholera outbreak (mentioned in your textbook). We’ll actually read a book 2 nd semester on this.  See right how overlaying data communicates data differently.

MAP PROJECTIONS  The only way that a the Earth’s surface can be accurately represented is through a globe. (3 dimensional)  Otherwise; the Earth’s surface is represented on a projection.  When you draw the Earth (sphere) on a 2 dimensional piece of paper it creates distortion.  ALL maps have distortion! There are four types of a distortion, a map can only eliminate three at most.

4 TYPES OF DISTORTION  Shape: “appears more elongated or squat than in reality”  Distance: “between two points may become increased or decreased.”  Relative Size: “one area may appear larger than another on a map but is in reality smaller.”  Direction: “from one place to another can be distorted” (Rubeinstein, 2014, p. 9).

MAP TYPES/DISTORTION EXAMPLES  Mollweide Projection  Sizes are true, but distorts shapes.

 Azimuthal  Distorts direction  Distances are correct only from the center.  Shape is distorted

 Mercator  One of the most common maps  Direction is true  Shape of landmass is true  Size is distorted (mostly along top, where less people live)  Used in navigation

 Robinson Projection: What’s in your textbook.  All four areas are distorted in an attempt to create balance.

SCALE  Scale answers the question of how much of the Earth’s surface to show on a map.  Map scale will influence the detail and amount of area covered.  Map scale is presented in three ways:  Ratio or fraction: Shows numerical ratio between distances on the map and Earth’s surface 1/24,000 means one unit  Written scale: describes the relationship between map and earth distances in words; example 1 inch equals 1 mile on the map.  Graphic scale: Bar line marked to show the distance.

SCALE

USES OF MAPS: CARTOGRAM These are sulpher emissions per country. Countries are displayed larger based on the amount that they represent.

MAPS LIE  Maps often reflect the bias of the mapmaker; it’s not always bad, they may eliminate things to emphasize other areas.  Sometimes, poor color choices, and how data is reported; it’s intentional to mislead the viewer or reader.  Sometimes map lie because they simply aren’t clear.  Maps are often chosen based on the emotion that one is seeking to evoke with them; especially when used in political advertisements or in public speaking.

PRESIDENT RONALD REGAN ALWAYS USED MERCATOR PROJECTIONS WHEN TALKING ABOUT THE U.S.S.R. (RUSSIA)