Maps And Globes Are Models Of The Earth

1.2Maps and globes are models of

Earth.

Maps show natural and human-made features.

• Any map you use is a flat model of Earth’s surface, showing features as seen from above.

• A globe represents Earth as it is seen from outer space. It shows relative sizes and shapes.

Land Features on Maps• A relief map shows how high or low each

feature is on Earth.

mountains

plateaus

plains

• Mountains- stand higher than the land around them. A group of mountains is called a mountain range. A group of mountain ranges is called a mountain belt.

• Plateaus- have fairly level surfaces but stand high above seal level. Often found near mountain ranges.

• Plains- gently rolling or flat land features. The U.S. has two types of plains: coastal and interior.

Scale and Symbols on Maps• The maps most often used are road and city

maps.

• A map scale relates distances on a map to actual distances on Earth’s surface. A scale can be expressed as a ratio, a bar, or equivalent units of distance.

• A map legend, also called a key, is a chart that explains the meaning of each symbol used on a map.

compass rose

Latitude and Longitude show locations on the Earth

• Latitude is based on an imaginary line that circles the Earth halfway between the north and south poles called the equator.

• Latitude is a distance in degrees north or south of the equator, which is 0 degrees.

*Notice that the north and south poles are at 90 degrees N and south latitude.

• Longitude is a distance in degrees east or west of the prime meridian, which is 0 degrees. The prime meridian stretches from the north to the south pole through Greenwich, England.

*You can find a location by noting where latitude and longitude lines cross.

Global Positioning System (GPS)• A network of 24 satellites that find the

latitude, longitude, and elevation of any site. • A computer inside a receiver uses the satellite

signals to calculate the user’s exact location. • Used by: pilots, drivers, sailors, hikers, and

map makers.

Map Projections• Distort the view of

Earth’s surface.• Projection- a way of

representing Earth’s curved surface on a flat map.

• Cylindrical projection (Mercator)

Problem: They make areas farther away from the equator appear larger than they are.

• Conic projections are based on the shape of a cone.• When the cone is flattened out, the latitude lines are

curved slightly. • Most useful for mapping large areas in the middle

latitudes, such as the U.S. • Problem: Distortion of landmasses near the equator

and the poles.

• Planar projections- Developed to help people find the shortest distance between two points.

• Drawn as if a circle of paper were laid on a point on the Earth’s surface.

• Sphere shape transferred to a flat map.

• Good for plotting ocean or air voyages.

• Problem: Landmasses farther away from the center point are greatly distorted.

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