# 1.1 Introduction to Maps and Types of Maps

#maps

written by

sana fatah

June 1, 2020

## Map Scale and Projection

Have you ever seen a map the size of America? Or the size of the world? No? Then how are maps accurate if they are not the same size as the area they’re representing? That’s where scaling comes into play.

A map scale presents the map’s features in relation to the actual size on the Earth. The three most common forms are:

1. Ratio

1. 1 : 25,000

2. The number on the left of the ratio is always the units of distance on the map

3. The number on the right is always the unit of distance on Earth’s surface

4. Every 1 inch on this map represents 25,000 actual inches on Earth’s surface.

2. Written scale

1. “1 inch equals 1 mile”

2. Explains the relationship in words

3. Graphic Scale

1. There is a bar line marked on the map to show how much actual distance is covered

Okay, so there’s a good reason why maps aren’t as big as the actual area they are depicting. But how does a flat, 2D map on a piece of paper accurately represent our spherical Earth?

• Projection: transferring locations on Earth’s surface to a flat map

Depending on what the cartographer wants to focus on, they have these four choices to make sure the globe fits on a paper:

1. The shape of an area can be distorted

2. Distance between two areas is inaccurate

3. The relative size of different areas is inaccurate

4. Direction can be distorted

### Two Types of Projections:

Robinson projection

+ used to focus on oceans

- land masses are smaller

Image Courtesy of The Guardian

Mercator projection

+ Accurate shape and direction

+ Map is rectangular

- Size of poles are distorted

## Geographic Grid

There are imaginary grid patterns drawn on Earth’s surfaces that tell us specific locations.

• Parallel: arcs in circles around the LAP of the earth

• Location of parallels is indicated by latitude

• LATitude → LAT=LAP= horizontal

• Your LAP is horizontal. So latitude is horizontal.

• Meridian: arcs drawn from the North pole to the South pole

• Location of meridians is indicated by longitude

• LONGitude → LONG= up and down

• If something is long, it is vertical. So longitude is vertical.

Latitude and longitude are used together and give us a specific coordinate and location.

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