1. Types of Maps

2. • Cartography is the science of mapmaking.
• For thousands of years, people have used maps
to define borders and to find places.
What is a Map?
•A map is a graphic
representation or scale model
of spatial concepts.
•It is a means for conveying
geographic information.
• Old maps provide much
information about what was
known in times past, as well
as the philosophy and
cultural basis of the map,
which were often much
different from modern
Mapping the Earth

3. 1. Geologic Maps – displays geologic features (rock type).

4. a. Topographic Maps – maps that show shape
and elevation of the Earth.

5. 2. Bathymetric
Maps – displays
oceanic features
(seafloor
topography,
currents, salinity,
temperatures).

8. 3. Weather maps – displays atmospheric conditions

9. Latest ISOTHERMS
Isotherms – lines of equal temperatures.

10. Isobars – lines of equal air pressure.
Latest ISOBARS

11. 4. Astronomical
Maps – displays
location of
object in space
(planets, stars,
comets,
ect…).

13. Other types of Maps

14. Types of Maps (underline the following)
• Maps are flat models of a three-dimensional
object, Earth.
Types of Maps
• All flat maps distort to some degree either the
shapes or the areas of landmasses.
• Cartographers use projections to make maps.
• A map projection is made by transferring points
and lines on a globe’s surface onto a sheet
of paper.

15. 1. Projections
• A Mercator projection shows parallel lines of
latitude and longitude.
Types of Maps
• In a Mercator projection, the shapes of the
landmasses are correct, but their areas
are distorted.

16. 2. Conic Projections
• A conic projection a map made
by projecting points and lines from
a globe onto a cone.
Types of Maps
• The cone touches the globe
at a particular line of latitude
along which there is very little
distortion in the areas or
shapes of landmasses.
• Distortion is evident near
the top and bottom of the
projection.

17. 3. Gnomonic Projections
• A gnomonic projection - a map made by taking a
picture from the north or south pole.
Types of Maps
• Gnomonic projections distort direction and distance
between landmasses.
• Gnomonic projections
are useful in plotting
long-distance trips by
air or sea.

18. Map Scales
and
Legends

19. • A map legend explains what
the symbols represent.
Map Legends
• Topographic maps and most
other maps include both human-
made and natural features that
are located on Earth’s surface.
• These features are represented
by different symbols.
Types of Maps

20. • A map scale is the ratio between distances on a
map and actual distances on the surface of Earth.
Map Scales
• When using a map, you need to know how to
measure distances.
Types of Maps

21. Map Scales
• There are three types of map scales: verbal
scales, graphic scales, and fractional scales.
Types of Maps
– A verbal scale expresses
distance in voice, such as
saying, “One centimeter is
equal to one kilometer.”
– A graphic scale – a picture
that represents a certain
distance, such as 5 km or 5
miles.
– A fractional scale expresses
distance as a ratio,
such as 1:63 500. (1 inch
equals 63,500 INCHES)

22. Satellites
&
Infrared imagery

23. Remote Sensing
• Until recently, mapmakers had to go on-site to
collect the data needed to make maps.
Remote Sensing
• Today, advanced technology has changed the
way maps are made.
• The process of collecting data about Earth
from far above Earth’s surface is called
Remote sensing (Satellites).

24. 1. Satellites
• A Landsat satellite uses wavelengths of light
including infrared radiation to produce an image.
Remote Sensing
• Since the features on Earth’s surface radiate
warmth at slightly different frequencies, they
show up as different colors in images
Landsat Images

26. Landsat image of Virginia

27. Virginia Beach – Landsat image.

28. 2. Topex/Poseidon Satellite
• The Topex/Poseidon satellite uses radar to map
features on the ocean floor.
Remote Sensing
• Radar uses high-frequency
signals that are transmitted
from the satellite to the
surface of the ocean.
• A receiving device then
picks up the returning
echo as it is reflected off
the water.

32. 3. The Global Positioning System
• The Global Positioning System, or GPS, is a
radio-navigation system of at least 24 satellites
that allows its users to determine their exact
position on Earth.
Remote Sensing
• Each satellite orbits Earth and transmits high-
frequency microwaves that contain information
about the satellite’s position and the time of
transmission.
• A GPS receiver calculates the user’s precise
latitude and longitude by processing the signals
emitted by multiple satellites.

33. 4. Sea Beam
• Sea Beam technology is similar to the Topex/
Poseidon satellite in that it is used to map the
ocean floor.
Remote Sensing
Sonar (SOUND NAVIGATION AND RANGE) is
the use of sound waves to detect and measure
objects underwater.

34. Sea Beam
• First, a sound wave is sent from a ship toward the
ocean floor.
Remote Sensing
• A receiving device then
picks up the returning
echo when it bounces
off the seafloor.
• Computers on the ship
can then calculate the
distance to the ocean
bottom based on the
time it takes the signal
to be reflected.

35. Latitude
and
Longitude

36. • Cartographers use an imaginary grid of parallel
lines and vertical lines to locate points on Earth.
• The equator circles Earth halfway between the
north and south poles separating Earth into two
equal halves called the northern hemisphere
and the southern hemisphere.
Latitude and Longitude
Latitude and Longitude

37. Latitude
• Lines of latitude are lines running parallel to
the equator.
Latitude and Longitude
• Latitude is the distance in
degrees north or south of
the equator.

38. Latitude
• Latitude is thus measured from 0° at the equator
to 90° at the poles.
Latitude and Longitude
• Locations north of the
equator are referred to
by degrees north
latitude (N).
• Locations south of the
equator are referred to
by degrees south
latitude (S).

39. Latitude
Degrees of Latitude
Latitude and Longitude
– Each degree of latitude is equivalent to about
111 km (°) on Earth’s surface. 1° = 70 miles
– To locate positions on Earth more precisely,
cartographers break down degrees of latitude into
60 smaller units, called minutes (´). 1' = 1.2 miles
– A minute of latitude can be further divided into
seconds (´´). 1" = .02 miles
– Longitude is also divided into degrees, minutes,
and seconds.

40. Longitude
• To locate positions in east and west directions,
cartographers use lines of longitude, also known
as meridians.
Latitude and Longitude
• Longitude is the distance in
degrees east or west of the
prime meridian.
• The prime meridian,
representing 0° longitude,
is the reference point for
longitude.

41. Longitude
• Points west of the prime meridian are numbered
from 0° to 180° west longitude (W).
Latitude and Longitude
• Points east of the prime
meridian are numbered from
0° to 180° east longitude (E).

42. Longitude
Semicircles
Latitude and Longitude
– Lines of longitude are not parallel; they are large
semicircles that extend vertically from pole to pole.
– The distances covered by
degrees of longitude vary
with location.
– One degree of longitude
varies from about 111 km
at the equator to essentially
the distance covered by a
point at the poles.
Degrees of Longitude

43. Longitude
Locating Places with Coordinates
Latitude and Longitude
– Both latitude and longitude
are needed to precisely
locate positions on Earth.
– For example, the location
of New Orleans is
29°57´N, 90°04´W.
– Note that latitude comes
first in reference to the
coordinates of a
particular location.

44. Time Zones

45. Time Zones
Calendar Dates
Latitude and Longitude
– Every time zone experiences this transition from one
day to the next, with the calendar advancing to the next
day at midnight.
– Each time you travel through a time zone, you gain or
lose time, eventually gaining or losing an entire day.
– The International Date Line, or 180° meridian, serves
as the transition line for calendar days.
– Traveling west across the International Date Line, you
would advance your calendar one day.
– Traveling east, you would move your calendar back
one day.

46. Time Zones
• Because Earth takes about 24 hours to rotate
once on its axis, it is divided into 24 times zones,
each representing a different hour.
Latitude and Longitude

47. Time Zones
• Each time zone is 15° wide, corresponding
roughly to lines of longitude.
Latitude and Longitude
• Time zone boundaries have been adjusted in
local areas for convenience.

48. Time Zones
• There are six
different time
zones in the
United States.
Latitude and Longitude