Tools of GeographyMaps and Projections

Let’s See What You Know About Maps….

• Look at the Map….

• In the next minute, write down as many characteristics you can think of about the map….

WHAT IS A MAP?• Maps are a visual representation of

the Earth’s surface, drawn to scale and made for a specific purpose.

• Maps have show 4 different properties:– Size -Shape– Distance -Direction

NOTE: All maps show these 4 properties but they can’t all be accurate at the same time on a map.

Making Money with Maps• A person who makes maps is called a CARTOGRAPHER.

1000 BC. 150 A.D. 1500s A.D. 2000s A.D.

Middle East-The Babylonians used clay tablets that depicted the Earth as a flat circular disk.

Ancient Greece-Ptolemy believed the sun to circle around the Earth. His methods of coordinates and projections are still used today.

Europe-Mercator created his map called the Mercator Projection. This helped mariners sail to their destinations using a fixed rule called a thumb line.

World Wide-Aerial photographs, computers, electronic distance-measuring instruments, inertial navigation systems, remote sensing, and applications of space science create new extensions of cartography's reach. The Internet makes that reach accessible to all of us.

Physical Maps

• Physical Map- This type of map uses colors to show elevation and other land/water features of the earth. This map may also show any physical feature such as mountains, oceans, rivers, valleys, etc.

• Topographic Maps are physical maps in 3D forms.

Political Maps• Political Map- this is

a map that shows political boundaries, borders, area of political entities (countries, states, territories, districts, zones, counties, provinces, etc) These types of maps may also show capitals/ other cities.

Thematic MapsWhat is the map of Texas about?

Thematic Maps

• This type of map shows “themes” or subjects on a map- basically any information. Anything can be shown on a map using symbols, colors, pictures, numbers, contour lines, etc. ALL THEMATIC MAPS MUST HAVE A KEY- this tells the reader what each picture/symbols/color/etc represents on the map i.e. + represents a hospital

Parts of a Map

• Key/ Legend: Shows information as symbols• Scale: Used for measuring distance (like a

ruler) • Scale can also be shown in ratio form (ex. 1:10)

or by an equation (ex. 1 inch = 10 miles)• Directional Arrow: All maps must have AT

LEAST an arrow showing relative direction. This is called orientation

• Compass Rose: Shows Cardinal & Intermediary Directions

N

WHICH ONE IS WHICH???

TODALS

•T = Title•O = Orientation•D = Date •A = Author•L = Legend (Key) •S = Scale

Other Geographic Tools…GIS (Geographic Information Systems) is the most accurate to

date: GIS is using computers to plot points and other information on maps.

Air Photography and Satellite Images can help gather information to then be placed on maps. Cartographers can interpret what they see and plot it on a map.

GPS (Global Positioning Systems) use satellites around the world to plot the exact point of location from an electronic receiver.

Nautical charts are used to navigate ships and boats. Nautical charts show water depths, lighthouses, buoys, islands, and

such dangers as coral reefs and underwater mountains. Atlases are collections of charts, graphs, and maps that we can

use to look up many different characteristics about a place on Earth.

Example: Google Earth

Map Projections

• To find just the right map to use, ask yourself “What am I trying to show on my map?”

• You don’t want to use a map that has too much distortion (being mis-shapen on a map)

• Usually you ask the question for one of the following four map topics:

» AREA» DIRECTION» DISTANCE» SHAPE

TYPES OF MAP PROJECTIONS

BONUS TRACK…

• What is the best way to represent the Earth????

Still Thinking….

A GLOBE!

• A globe shows the location and shape of geographic areas exactly as they are on earth.

COPY THIS CHART!!!!

Projection Picture Good and Bad?

Mercator Map Projection

• Mercator Map Projection: Shows accurate direction, but area & shapes are severely distorted at the poles. Mercator projections are based on cylinders.

• ***Sailors would use these for true direction

Look how big I am on a Mercator Map!!!

Robinson Map Projection • Robinson Map Projection: Shows

accurate shape & size of continents, but water areas are expanded to fill in area. Robinson projections are based on ovals. ***These maps are good for data collections like in a classroom or lab.

Interrupted Map Projection• Interrupted Map

Projection: Shows accurate area & shape of continents, but oceans have open pie-shaped wedges are to adjust for distance.

Why does my projection

look so much different

from all the others? …..

(sniff)….I want to have a

nice and even shape, too!

CONICAL Map Projection

• Conical Map Projection: Used for mapping a large piece of Earth's surface. It shows accurate distance, direction, & shape for the limited area mapped. Conical projections are based as cone-shape.

It’s CON-i-cal…. not COM-i-cal…even

though it DOES look like I have a dunce cap on my head!

AZIMUTH (aka POLAR) Map Projection

• Polar Map Projection: Used for mapping hemispheres instead of whole Earth. Shows accurate distance & direction but shape and size are distorted at the edges. Polar view is called Azimuth.

• ***Airline Pilots would use these maps to follow Great Circle Routes (the shortest path between two points along the curve of the Earth)

Just call me “polar” since I only show one pole at a time. It sure

beats being confused with “asthma” maps!!!

WHY USE DIFFERENT KINDS OF MAPS/PROJECTIONS?

• DIVERSITY!• Can’t show a whole earth/global view

on any one map.• Each projection suits a different

purpose• Globes are bulky (and hard to fit in

your folder!) and can’t show the whole earth at one time.