maps and globes are models of the earth
TRANSCRIPT
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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