Websites

http://www.teachertube.com/viewVideo.php?video_id=188367&title=Map_Projections_Intro

Warm-up #6Jan. 13

TOPOGRAPHY Maps that show

elevation of the Earth’s surface by means of contour lines

Can also show the presence of bodies of water, roads, and buildings.

Who might find these maps beneficial ?

What types of problems would a mapmaker have when designing a flat map of the globe?

Maps and MappingChapter 1

Warm-up #10 Jan. 24

On a topographic map, contour lines that form a circle indicate a hill.

Lines with hatch marks indicate a depression.

Question How could two points 35 degrees

north of the equator – one in N. America and the other in china – be distinguished using map coordinates?

Finding Locations of Earth Latitude – imaginary parallel lines

that measure angular distance north and south of the equator

Longitude – imaginary lines that measure angular distance east and west

Great Circles

Any circle that divides the globe into halves.

Used often in navigation because a great circle is the shortest distance between two points on a sphere.

Map Projections

A flat map that represents the three dimensional surface of a globe.

Four common projections Mercator Gnomonic Conic Robinson

Mercator Projection

If you were to wrap a cylinder of paper around a lighted globe the Mercator projection is what you would see.

Has advantages and disadvantages.

What do you think are some disadvantages?

Gnomonic Projection

A sheet of paper touching a lighted globe at only one point produces a gnomonic projection.

There is little distortion at the point of contact, but unequal spacing between parallel lines causes distortion on both direction and distance further out.

Conic Projection

A paper cone placed over a lighted globe so that the axis of the cone aligns with the axis of the globe will produce a conic projection.

Robinson

One of the most widely used Very similar to the Mercator Less distortion than Mercator

Map Projections Mercator: accurate direction, distortion

of size and distance. Gnomonic: accurate at point of

tangency, large distortion further out. Conic: accurate over a small region,

inaccurate over long range. Robinson: accurate in direction, less

distortion of size and distance than mercator.

Sample Maps

http://maps.google.com/maps?hl=en&tab=wl

Google Earth

Reading a Map

Symbols: used to represent items on the map

Legends: explains the symbols Map Scale: Ratio that shows the

proportions of the map 1:300 means that one of the measuring

units equals 300 of that unit. 1 cm on the map = 300 cm on actual

surface

Topographic Maps

Shows surface features Topography is the study of these

features Contour lines tell you the difference

in elevation The ones that form a circle represent a

hill They should never touch or intersect

Playdoh Mountain Lab

READ THE DIRECTIONS CAREFULLY On the back, create a side view diagram

of your mountain (just like the one on the worksheet)

In your journals: Describe your landmass What type of intervals did you use? What does it mean when your lines are

closer? Farther apart? Answer Step 6

Warm-up #7 Jan. 19

Meridians Used to establish east-west locations They are semi-circles reaching around

the earth from pole to poleTrue North

The direction of the geographic North Pole

Do you think that a compass points to the true north? If not then what?

Review

What do the these lines represent?

Tropics

What are the two tropic lines of latitude that surround the equator? Tropic of Cancer ▪ 23 °North of the Equator

Tropic of Capricorn▪ 23 ° South of the Equator

Where does the Prime Meridian lie? 0 ° Longitude

Review Great Circles

Cuts the world in halves

Used for navigation because they show the shortest distance between 2 points

Review

Remember your 4 map projections Mercator Gnomonic Conic Robinson

Topography

What are these maps used for? Elevation, surface features

What do the contour lines represent? The elevation at that point

The difference in elevation between one contour line and the next is the contour interval

Warm-up #8 Jan. 20

How to Read Longitude/Latitude Lines: Always list the latitude degrees (N and

S) followed by the longitude degrees (E and W)

Ex: The white house is located at 36° N, 86° W

Angular distance between the equator and the north pole is 90 degrees What about between East and West of

the Prime Meridian?

Tax Maps

In your journals, I want you to describe the surface features where you live: Elevation Wooded area/ roads/ streams Etc.

Look at both topo and arial maps When you are done compare where

you live with the person next to you

Finding Direction

What’s one way to find direction? A magnetic compass works because

earth has magnetic properties

Points on the earth’s surface just above the poles of the imaginary magnet are called the geomagnetic poles. Because of the tilt, geomagnetic poles

and geographic poles are in different places

Geomagnetic Poles

Magnetic Declination

The angle between the direction of the geographic pole and the direction the compass needle points is called magnetic declination

Magnetic Declination

If you move East of the Mississippi River, the magnetic north pole will pull your compass needle further to the West of geographic north The angle of compass declination is

West Declination Moving west of that line will pull your

compass needle further to the East East Declination

TICKET OUT THE DOOR

1. What lines measure distances North of South of the equator?

2. What is the line of longitude at 0°?3. What are the four types of map

projections?4. What information is shown on a

topographic map?