Warm Up Journal 09/05

1. The lines on the map to the right indicate _________________ .

2. Explain the difference between rotation and revolution?

3. How would an increase in the rate of Earth’s rotation affect the length of a day?

4. What causes seasons?

Warm Up Journal 09/051. The lines on the map to the right indicate

___longitude__ .2. Explain the difference between rotation and

revolution? Rotation spinning on axis, revolution is moving around another object

3. How would an increase in the rate of Earth’s rotation affect the length of a day? Days would be shorter

4. What causes seasons? The angle at which the sun’s rays strike the surface of the earth

3.2 & 3.3

Mapping the Earth’s Surface

Map Projections

• Cartography: the science of making maps• A cartographer is a map maker.

Journal Question : What might be some challenges in representing the Earth’s surface accurately?

Challenge of making maps…

• Transferring a curved surface into a flat representation!

• Map projection: a flat map that represents the 3 dimensional curved surface of a globe

3 common map projections– Mercator– Gnomic– Conic

• Mercator Projection– Meridians are evenly spacedParallels are closer at the equator and further apart at the poles

– Accurate near equator, but distorts the map at the poles

– Useful because:• longitude and latitude are on a grid• Shapes of small areas are accurate

• Gnomic Projection– Projection from the point of view of one point

(usually a pole)– Accurate at the point of contact but distortion

increases further away from the contact.

– Useful in planning air travel

• Conic Projection– Projection created when a paper cone is placed

over a globe

JournalWhat are a couple of things that are useful to

you when interpreting the map pictured below?

Reading a Map

• Legend: a list of symbols and their meanings

• Compass: direction on a map

• Map Scale: indicates the relationship between distance shown on the map and actual distance.

Topographic Maps

• Show surface features, topography.– Rivers– Hills– Buildings– Roads

Elevation: height above sea level– Measured from mean sea level = 0

Contour Lines: lines that show elevation– Any point along a line is at the elevation indicated

by the map

Contour Intervals: The difference between one contour line and the next.

Journal # 7 : If the contour Interval is 15 meters, what is the elevation at point Y and at Point X?

-x -Y

0 meters (sea level)

Landforms on Topo Maps• Journal #8 : What might be indicated when

contour intervals are very close together?

Depression Contours: show that an area is decreasing in elevation

• Journal: What land features may require a depression contour when shown in a topographic map?

Time to practice with Contour Maps!!!