2. Maps, Globes, and how to
read them:
• Maps and globes are
drawn to scale.
• Scale - relates distance
on a map to distance on
the earth’s surface.
3. Scale-Three Types:
1. Ratio Scale: For example, one unit on a map
could equal 100,000 units on the ground.
2. Bar Scale: is a line drawn on a map of known
ground length.
3. Equivalent Units Scale: states what distance on
a map is equal to what distance on the ground
4. • To locate points on a map or globe,
we use the equator, the prime
meridian, and longitude and latitude
lines.
• The units in which points are
measured are in degrees (angular
distances calculated from the center
of the Earth)
• To give an exact location, a degree
can be broken down into 60 minutes,
and a minute broken down into 60
seconds.
5. • The earth is divided into lines called
latitude and longitude.
6. • Longitude lines run vertically (north and south.)
• Latitude lines run horizontally (east and west.)
*LATitude is FLAT, LONGgitude is LONG*
7. • The equator is an imaginary line that
runs HALFWAY BETWEEN the North
Pole and the South Pole. It is 0
degrees latitude.
• The equator divides the earth into a
northern and a southern hemisphere.
Equator
8. • The prime meridian is
an imaginary line that
runs FROM the north
pole to the south pole.
It is 0 degrees
longitude.
• The prime meridian
divides the earth into
eastern and western
hemispheres.
9. •There is a marker
showing the actual
location of the Prime
Meridian in
Greenwich, England.
10.
11. Prime Meridian
N • Lat/Long are 2 grid
points or coordinates
by which you can
locate any point on
W E earth!
Equator • The four quarters
of a world map can
be designated by
S North or South and
East or West.
12. • N tells us we’re north
(N, W) (N, E)
of the Equator. S tells
us we’re south of the
Equator.
• E tells us that we’re
east of the Prime
Meridian. W tells us that
(S, W) (S, E)
we’re west of the Prime
Meridian.
13. • Latitude is
90 N
Y always
measured in
degrees North or
X
South because it
is either north or
south of the
equator.
90 S
14.
15. Y
• Longitude is
always measured
in degrees East X
or West because
it is East or West
of the prime
meridian.
180 W 180 E
16. (N, W)
• That means all points in
North America will have
a North latitude and a
West longitude because
it is North of the Equator
and West of the Prime
Meridian.
Prime Meridian
17. •What would be
the latitude and
longitude
directions in
Australia?
Prime Meridian
Latitude: º South
Longitude: º East!
18. Long or Lat?
•Is 30º East a Longitude
or Latitude?
Longitude
•Is 60º South a Longitude
or Latitude?
Latitude
19. Which Quarter are These Lon/Lats
Located In?
0 degrees latitude = equator 1. 41 N, 21 E
1. B
2. 37 N, 76 W
2. A
3. 72 S,141 W
3. C
A B 4. 7 S, 23 W
4. C
5. 15 N, 29 E
C D 5. B
6. 34 S, 151 E
6. D
0 degrees longitude = prime meridian
20. • For centuries, maps were drawn by
hand.
• Mapmakers determined distances and
elevation using instruments in a
process called surveying.
• Now, computers are used to make
maps.
• Where do computers get the
information to make maps?
21. • Satellites that orbit the earth obtain
information which assists with
mapping (finding elevation, latitude
longitude, and ground covering),
measure environmental change,
determine urban growth, etc.
• The Landsat satellite program
began in 1972.
• Landsat satellites collect Landsat satellite
information which is used to make
digital satellite images.
22.
23. • Landsat satellites record radiation from the
surface of the earth in different wavelengths of
the electromagnetic spectrum. Much of this
radiation we cannot see (ex. infrared).
• Computers create images from the radiation and
add ―false-color‖ to the wavelengths that we can
not normally see. We can learn to identify
specific features by the colors of a satellite
image.
• Grass, trees, crops-red
• Water-black or blue
• Cities-bluish gray
24. • GPS (Global
Positioning System) is
a system of satellites
that can be used to
make maps.
• 3 or 4 satellites are
needed to pinpoint
the longitude, latitude,
and elevation of a
location.
28. • A topographic map is a map showing the surface
features of an area.
• Who would find topographic maps useful?
• Geologists, hikers, park rangers, engineers, government
agencies, etc…
29. • Lines on the map are
called contour lines
• Contour lines connect
points of equal
elevation
• Mapmakers use
contour lines to
represent
elevation, relief and
slope.
31. • Never cross each
other
• Connect with
themselves
• Get closer together
as land gets steeper
• Get further apart as
land gets flatter
32. •Contour interval- A
contour interval is the
difference in elevation
between two contour
lines that are side by
side.
•The contour interval is
always the same for the
whole map.
•What is the contour
interval for this map?
•25 meters.
33. • An index contour—every 5th contour line—
is darker and heavier than the others and
is labeled with the elevation in a nice
round number.
34. • To read a topographic map, you must
familiarize yourself with the map’s scale,
symbols, colors and interpret the map’s
contour lines.
35. • Blue lines/shapes - represent water features, such as
streams and lakes.
• Brown – contour lines
• Black – Roads, buildings, railroads, other man made objects.
• Green – Woodland areas
• Red - Highways
36. • Look for areas where the contour lines are close
together – they indicate a steep area.
• Look for areas where the contour lines are spread apart
– they indicate a gentle slope.
• Easily visible closed loops indicated a hill top.
• Dashed lines indicate a depression (a ―hole‖ in the
ground), such as a caldera (collapsed volcano)
Steep Slope
Gentle Slope
37.
38. • V-shaped
contour lines
pointing uphill
(to a higher
elevation) are
valleys.
• A stream in a
valley flows
toward the open
end of the V.
39. Review Questions
• How are contour lines drawn on maps?
– Connect points of equal elevation, never intersect,
form loops although not always visible.
• How does a contour map show whether a slope is gentle
or steep?
– Steep- lines close together
– Gentle- lines far apart
• V-shaped lines pointing uphill indicate a ___________.
Valley
• How do you know which way the water is flowing in a
valley stream?
– Water flows toward open end of the V.
