1. Ch.2: Mapping Our World
Text ref. (pg.26)

2. Contents
Latitude and Longitude
Types of Maps
Remote Sensing

3. Latitude and Longitude
Text ref. Ch.2.1, p.27-31

4. Objectives Compare and contrast latitude and longitude.
Describe how time zones vary.

5. Cartography Science of mapmaking.
Use a series of imaginary grid of parallel lines and vertical lines
Equator circles Earth halfway between north and south poles

6. Latitude
Latitude is the distance in degrees north or south of the equator.
Equator is equal to 0° latitude
Poles are equal to 90° latitude
North latitude from equator to the North Pole.
South latitude from equator to South Pole.

7. Degrees of Latitude 1 degree of latitude is equal to about 111 km.
Cearth= km therefore, km/360 = 111 km.
Smaller units of measure for latitude include minutes ‘ and seconds “ .
Ex. Mobile is located at N latitude.

8. Longitude
Longitude is the distance in degrees east or west of the prime meridian.
The prime meridian represents 0° longitude.
Located through Greenwich, England
0° to 180° E and W of prime meridian

9. Semicircles Lines of longitude not parallel
Extend vertically from pole to pole
Line of longitude directly opposite the prime meridian equal to 180°
Known as International Date Line

10. Degrees of Longitude
Distance covered by degrees of longitude varies in relation to distance from equator.
Greatest at equator (111 km), approaches a point at the poles

11. Location with Coordinates
Latitude and longitude both needed for accurate global conditioning
Mobile: 30° 40' N 88° 15' W
San Francisco Co: 37° 46' N 122° 26' W
NYC-Central Park (S): 40° 47' N 73° 58' W
Tokyo: 35° 41' N 139° 46' E
Baghdad: 33° 20' N 44° 24' E

12. Time Zones
Earth divided in 24 time zones for each of the 24 hours of a day
Time zones 15° wide
U.S. spans 6 time zones

14. Calendar Dates
By traveling through time zones you gain or lose time until you gain or lose an entire day.
International Date Line located at 180° is the calendar line for days
Travel west across the International Date Line and you advance one calendar day, east across and you lose one calendar day.

15. Types of Maps
Text ref. Ch.2.2: p.33-36

16. Objectives Compare and contrast different map projections
Analyze topographic maps
Describe map characteristics, such as map scales and map legends.

17. Mercator Projections
Map that has parallel lines of latitude and longitude
Landmasses near poles are distorted, exaggerated
Ex. Greenland appears larger than Australia
Use: navigation of planes and ships

19. Conic Projections Made by projecting points from a globe onto a cone.
Very little distortion in landmasses and their sizes
Useful for smaller maps of regional areas, cities, and roadmaps.

21. Gnomonic Projections
Made by projecting points and lines from a globe onto a piece of paper that touches the globe at a single point.
Distort direction and distance between landmasses
Useful in planning shortest distance between two points by displaying Great Circles of longitude and latitude.

22. Topographic Maps
Show changes in the elevation of the Earth’s surface, as well as features such as mountains, rivers, forests, and bridges.
Use lines, symbols, and colors to represent changes in elevation.

23. Contour Lines on Topographic maps
Elevation on topographic maps represented by contour lines
Connects points of equal elevation
Contour lines never cross

25. Contour Intervals on Topographic maps
Used to show changes in elevation from one contour line to another
Mountains have greater contour intervals between contour lines than do plains or hills

27. Index Contours in Topographic Maps
Used to aid in interpreting the elevation of landmarks and terrain on a topographic map.
Marked by numbers representing elevation
For example, if contour interval is 10 m, you can subtract or add 10 m for each interval from the index contour to determine the elevation at that location.

28. Depression Contour lines in Topographic maps
To represent areas of lower elevation than their surroundings, depression contour lines will have hachures
Short lines at right angles to the contour line
Point toward the area with the lower depression.

29. Map Legends
Natural and human-made features are represented by symbols on maps

30. Map Scales
Defines the ratio between distances on a map and actual distances on the surface of Earth
Verbal: expresses ratio as a statement
Graphic: consists of a line that represents a certain distance.
Fractional: expresses distance as a ratio

31. Ch.2.3: Remote Sensing
Text ref. p 37-41

32. Objectives
Compare and contrast the different forms of radiation in the electromagnetic spectrum.
Discuss how satellites and sonar are used to map Earth’s surface and its oceans.
Describe the Global Positioning System

33. The Electromagnetic Spectrum
Arrangement of electromagnetic radiation according to wavelengths
Electromagnetic radiation (i.e. light)
Speed = km/s or mi/s
Types of EM radiation are defined by their frequency and wavelength
Frequency is the number of wavelengths that occur each second

37. Landsat Satellites
Receives reflected wavelengths of energy emitted by Earth’s surface
Infrared imaging allows for detailed images of lakes, rivers, forests, etc…
Mirrors based on satellite with light-sensitive detectors
Computer image conversion
Landsat , maps 185 km2
Can map the Earth in 16 days

41. Topex/Poseidon Satellite
Uses radar to map features of ocean floor
“Topex”= topography experiment
Beacons on ocean surface reflect high frequency radar send by Topex
Distance to water’s surface calculated by wave speed formula
v = λ x f

46. The Global Positioning System
GPS
Radio-navigation system of 24 satellites used to determine exact position on Earth
Originally devised by the military for strategic operations
Hand-held GPS unit can calculate the latitude and longitude of a location by processing signals of multiple GPS satellites.

50. GPS continued… Uses: Navigation of ships and planes
Earthquake detection
Map generation
Wildlife/ecology research

51. Sea Beam Technology used to map the ocean floor
Located on ship rather than satellite-based
SONAR technology used for mapping
Sound waves sent from ship bounce off ocean floor and return to receiver on ship. Distance calculated using wave speed formula

56. Uses of Sea Beam Fishing fleets Deep-sea drilling operations
Oceanographers
Volcanologists
Archeologists