CHAPTER 2CHAPTER 2

MAPPING OUR WORLDMAPPING OUR WORLD

Latitude & LongitudeLatitude & Longitude

Cartography – Science of Cartography – Science of mapmakingmapmaking..

Cartographers use an imaginary Cartographers use an imaginary grid of grid of parallelparallel lines and lines and verticalvertical lines to locate points on Earth.lines to locate points on Earth.

Latitude & LongitudeLatitude & Longitude

The The equatorequator circles Earth circles Earth halfway between the north and halfway between the north and south poles.south poles.

Above equator = Above equator = NorthernNorthern HemisphereHemisphere

Below equator = Below equator = SouthernSouthern HemisphereHemisphere

LATITUDELATITUDE Lines of latitude Lines of latitude

are lines are lines running running parallelparallel to the equator.to the equator.

Latitude is the Latitude is the distance in distance in degrees degrees northnorth or south of the or south of the equator.equator.

LONGITUDELONGITUDE Distance in Distance in

degrees degrees easteast or or westwest of the of the prime meridian.prime meridian.

Prime Meridian: Prime Meridian: Representing 0Representing 0° ° Longitude, it is Longitude, it is the the referencereference pointpoint for for longitude.longitude.

LONGITUDELONGITUDE Points Points westwest of of

Prime Meridian Prime Meridian are numbered are numbered 00°-180° W °-180° W Longitude.Longitude.

Points Points easteast of of Prime Meridian Prime Meridian are numbered are numbered 00°-180° E °-180° E Longitude.Longitude.

LONGITUDELONGITUDE To locate To locate

positions more positions more precisely, precisely, latitude and latitude and longitude are longitude are broken down broken down into into minutesminutes and and secondsseconds

Locating With CoordinatesLocating With Coordinates

Both Both latitudelatitude & & longitudelongitude are are needed to needed to precisely locate precisely locate positions on earth.positions on earth.

Latitude comes Latitude comes first, then longitudefirst, then longitude

Ex: New Orleans = Ex: New Orleans = 2929°57’ N, 90°04’ W°57’ N, 90°04’ W

TIME ZONESTIME ZONES Because Earth takes 24 hours to Because Earth takes 24 hours to

rotate once on its axis, it is divided rotate once on its axis, it is divided into into 2424 time zones. time zones.

Each time zone represents a Each time zone represents a differentdifferent hour. hour.

TIME ZONESTIME ZONES Each time zone is Each time zone is 1515°° wide. wide.

The US has The US has sixsix different time zones. different time zones.

International Date LineInternational Date Line International Date Line:International Date Line: 180 180° Meridian serves as ° Meridian serves as

transition for calendar days.transition for calendar days.

Traveling west = Traveling west = AdvancedAdvanced one day one day Traveling east = Move Traveling east = Move backback one day one day

TYPES OF MAPSTYPES OF MAPS

1. Mercator Projections1. Mercator Projections

Has parallel lines of Has parallel lines of latitudelatitude and and longitudelongitude.. Shapes of landmasses are correct, but Shapes of landmasses are correct, but

their their areasareas are distorted. are distorted.

2. Conic Projections2. Conic Projections

A map made by A map made by projecting points projecting points and lines from a and lines from a globe onto a globe onto a conecone..

Distortion is Distortion is evident near the evident near the toptop and and bottombottom of the projectionof the projection

3. Gnomonic Projections3. Gnomonic Projections

Map made by Map made by projecting points projecting points and lines from a and lines from a globe onto a piece globe onto a piece of paper that of paper that touches the globe touches the globe at a at a singlesingle point. point.

Distort Distort directiondirection and and distancedistance between between landmasses.landmasses.

4. Topographic Maps4. Topographic Maps

Maps showing the Maps showing the elevationelevation of hills and of hills and valleys.valleys.

Contour linesContour lines: : Connects points of Connects points of equalequal elevation. elevation.

Contour IntervalContour Interval: : Difference in elevation Difference in elevation between two side-by-between two side-by-side contour lines.side contour lines.

Index ContoursIndex Contours: : Contour lines marked Contour lines marked by their true by their true elevationelevation

Map LegendsMap Legends

Explains or depicts Explains or depicts what the what the symbolssymbols mean on a mean on a topographic map.topographic map.

Map ScalesMap Scales: Ratio : Ratio between the between the distances on a distances on a map and actual map and actual distances on distances on Earth’s surface.Earth’s surface.

Remote SensingRemote Sensing

Process of collecting data Process of collecting data about Earth far about Earth far aboveabove Earth’s surface.Earth’s surface.

Electromagnetic SpectrumElectromagnetic Spectrum Satellites detect different Satellites detect different

wavelengths of energy wavelengths of energy reflectedreflected or or emittedemitted from Earth’s surface. from Earth’s surface.

Ex: visible light, X rays, Ex: visible light, X rays, ultraviolet waves, infrared ultraviolet waves, infrared waves, radio waves, and waves, radio waves, and microwaves.microwaves.

Electromagnetic SpectrumElectromagnetic Spectrum

FrequencyFrequency: Number of waves that : Number of waves that pass a point each pass a point each secondsecond..

LANDSAT SATELLITESLANDSAT SATELLITES Receives reflected wavelengths of Receives reflected wavelengths of

energy energy emittedemitted by Earth’s surface. by Earth’s surface.

Topex/Poseidon SatelliteTopex/Poseidon Satellite: Uses : Uses radarradar to map features on the ocean floor.to map features on the ocean floor.