maps and map skills

Maps and Map SkillsMaps and Map Skills

Kinds of MapsKinds of Maps

• General Reference MapsGeneral Reference Maps

• Provide the reader general information Provide the reader general information about an area or place.about an area or place.

• Thematic MapsThematic Maps

• Provide more specific information about Provide more specific information about an area or place than general reference an area or place than general reference maps.maps.

General referenceGeneral reference

Thematic MapThematic Map

• Maps are important tools for Maps are important tools for geographers.geographers.

• A globe is a better model of A globe is a better model of Earth than a map, but a globe Earth than a map, but a globe has disadvantages that a map has disadvantages that a map does not havedoes not have

Reading MapsReading Maps

• Map PartsMap Parts• TitleTitle• Legend or KeyLegend or Key• Grid SystemGrid System• DirectionDirection• ScaleScale

• Map orientation – This has Map orientation – This has to do with directionto do with direction

Scale

Title

Compass

Large Scale and Small Scale Large Scale and Small Scale MapsMaps

• A large-scale map shows a small area such A large-scale map shows a small area such as a neighborhood street in great detail.as a neighborhood street in great detail.

• A small-scale map shows a large area such A small-scale map shows a large area such as a country or a continent in comparatively as a country or a continent in comparatively lesser detail.lesser detail.

Small Area = Large ScaleSmall Area = Large Scale

Large Area = Small ScaleLarge Area = Small Scale

Large ScaleSmall Scale

Small Area = Large ScaleSmall Area = Large ScaleLarge Area = Small ScaleLarge Area = Small Scale

CompassCompass

• Is used to orient a map toward northIs used to orient a map toward north

Latitude and LongitudeLatitude and Longitude

• Latitude Latitude • The set of lines crossing the Earth’s surface horizontally, The set of lines crossing the Earth’s surface horizontally,

Circling east and west. Circling east and west. • Each line of latitude is always an equal distance from the Each line of latitude is always an equal distance from the

next.next.• They are also known as parallels. All latitude lines are They are also known as parallels. All latitude lines are

parallel to each otherparallel to each other.

• LongitudeLongitude• A set of lines that run vertically along Earth’s A set of lines that run vertically along Earth’s

surface from the North Pole to the South Polesurface from the North Pole to the South Pole

Global GridGlobal Grid• When lines of latitude and longitude cross a grid is When lines of latitude and longitude cross a grid is

formed. The grid is used to located certain places on formed. The grid is used to located certain places on earthearth

• Each line has an Identifying number called Each line has an Identifying number called degrees, or parts of a circle. (41degrees, or parts of a circle. (4100

))

• Degrees, can be further divided into minutes, or Degrees, can be further divided into minutes, or parts of a degree. There are 60 minutes, or parts parts of a degree. There are 60 minutes, or parts of a degree. (10’)of a degree. (10’)

• Minutes can be divided into even smaller parts Minutes can be divided into even smaller parts called seconds. There are 60 seconds in each called seconds. There are 60 seconds in each minute. (10”)minute. (10”)

• 41410010’10”10’10”

414100

10’10’

10”10”

DegreesDegrees

MinutesMinutes

SecondsSeconds

DirectionDirection

• The other part needed to locate places on Earth is The other part needed to locate places on Earth is direction.direction.

• Cardinal directions are: north, south, east, and Cardinal directions are: north, south, east, and west.west.

• Intermediate directions are: northeast, Intermediate directions are: northeast, southeast, northwest, and southwest. They are southeast, northwest, and southwest. They are located midway between the cardinal located midway between the cardinal directions.directions.

Using Latitude & Longitude Using Latitude & Longitude to Locate Placesto Locate Places

• Lines of latitude are numbered based on how far Lines of latitude are numbered based on how far north or south they are from an imaginary line called north or south they are from an imaginary line called the equatorthe equator

• This line circles the Earth exactly halfway between This line circles the Earth exactly halfway between the NP and SP.the NP and SP.

• The equator’s latitude degree is 0The equator’s latitude degree is 000

. There are 90 . There are 90 degrees between it and each of the poles.degrees between it and each of the poles.• Area between the equator and NP is “north” latitude Area between the equator and NP is “north” latitude

(22(2200

N)N)• Area between the equator and SP is “south” latitude Area between the equator and SP is “south” latitude

(22(2200

S)S)

• Lines of longitude are numbered based on how far Lines of longitude are numbered based on how far east or west they are from another imaginary line.east or west they are from another imaginary line.

• This line is called the This line is called the Prime MeridianPrime Meridian..

• Prime Meridian’s longitude degree is 0Prime Meridian’s longitude degree is 000. .

• There are 180There are 18000 of longitude east of the PM and 180 of longitude east of the PM and 18000 degrees west of it.degrees west of it.• Area east of the PM is known as “east” longitude. Area east of the PM is known as “east” longitude.

(120(12000

E)E)• Area west of the PM is known as “west” longitude. Area west of the PM is known as “west” longitude.

(120(12000

W)W)

Prime Meridian & Prime Meridian & International Date LineInternational Date Line

• The prime meridian does not circle the The prime meridian does not circle the globe as the equator does.globe as the equator does.

• The PM runs from the NP to SPThe PM runs from the NP to SP

• At 180At 18000 on the other side of the globe the on the other side of the globe the meridian is called the international date meridian is called the international date line.line.

HemispheresHemispheres• The earth can be divided into halves. Each of these The earth can be divided into halves. Each of these

halves is called a hemispherehalves is called a hemisphere.

Hemispheres at the Equator Hemispheres at the Equator

• The ½ north of the equator The ½ north of the equator is called the northern is called the northern hemispherehemisphere

• The ½ south of the equator The ½ south of the equator is called the southern is called the southern hemispherehemisphere

Hemispheres at Prime Hemispheres at Prime Meridian and International Meridian and International

Date LineDate Line• Earth can also be divided into hemispheres Earth can also be divided into hemispheres

at the circle formed by the prime meridian at the circle formed by the prime meridian and International date lineand International date line

• The ½ east of the prime meridian is called The ½ east of the prime meridian is called the eastern hemisphere.the eastern hemisphere.

• The ½ west of the prime meridian is called The ½ west of the prime meridian is called the western hemisphere.the western hemisphere.

Making MapsMaking Maps

• Gathering InformationGathering Information

• Problem of DistortionProblem of Distortion

• Map PropertiesMap Properties

• Map ProjectionsMap Projections

• Cartographers (Mapmakers)Cartographers (Mapmakers)

Gathering InformationGathering Information

• SurveyingSurveying• Aerial Photography (Air Planes)Aerial Photography (Air Planes)• Remote Sensing (Satellites)Remote Sensing (Satellites)

Problem of DistortionProblem of Distortion• Features are stretched to put Features are stretched to put

Earth’s information onto a map.Earth’s information onto a map.

Map PropertiesMap Properties

• No map can have all of the properties at onceNo map can have all of the properties at once• Equal areasEqual areas• ConformalityConformality• Consistent ScaleConsistent Scale• True-Compass DirectionsTrue-Compass Directions

• Equal areasEqual areas• Places shown have the same proportions as they do Places shown have the same proportions as they do

on Earth. on Earth. • Example: Greenland 1/8 land area of S. AmericaExample: Greenland 1/8 land area of S. America

• ConformalityConformality• Having correct shapes.Having correct shapes.• Shows true shapes.Shows true shapes.• Can show larger areas as closely as possible to Can show larger areas as closely as possible to

their true shapestheir true shapes

• Consistent ScaleConsistent Scale• Uses the same scale for all parts of the map.Uses the same scale for all parts of the map.• Shows the true distances between places on EarthShows the true distances between places on Earth• In most Cases maps showing large areas cannot be In most Cases maps showing large areas cannot be

consistent-scale maps.consistent-scale maps.

••True-Compass DirectionTrue-Compass Direction• Parallels and meridians Parallels and meridians

appear as straight lines.appear as straight lines.• By following these lines By following these lines

you will be following the you will be following the cardinal directions of cardinal directions of N,S,E,&W.N,S,E,&W.

• Straight line between two Straight line between two points on map determines points on map determines exact directions and set exact directions and set course. (Navigators use course. (Navigators use these maps)these maps)

Map ProjectionsMap Projections

• Cylindrical ProjectionsCylindrical Projections

• Conic ProjectionsConic Projections

• Flat Plane ProjectionsFlat Plane Projections

• Gnomonic ProjectionGnomonic Projection

• Robinson ProjectionRobinson Projection

• Goode’s InterruptedGoode’s Interrupted

Cylindrical ProjectionsCylindrical Projections• Straight lines of latitude and Longitude are Straight lines of latitude and Longitude are

PerpendicularPerpendicular• Little distortion near the equatorLittle distortion near the equator• Best Known:Best Known:

• Mercator –Mercator –

• conformal and true-compass direction map, but conformal and true-compass direction map, but distortion near poles makes size of land and water areas distortion near poles makes size of land and water areas inaccurate. Land shapes correct – areas distorted – inaccurate. Land shapes correct – areas distorted – valuable to navigatorvaluable to navigator

Conic ProjectionsConic Projections• Cannot map the entire world.Cannot map the entire world.• Used for middle latitudes betweenUsed for middle latitudes between 303000 and 60and 6000 north north

latitudes, and betweenlatitudes, and between 303000 and 60and 6000 south latitudessouth latitudes• Best Known:Best Known:

• Lambert Conformal Conical Lambert Conformal Conical • Important because it shows the true shapes of Important because it shows the true shapes of

areas.areas.• Albers Equal Area ConicalAlbers Equal Area Conical

• Consistent scale and is used when the size of Consistent scale and is used when the size of land and water areas must be accurate. (military land and water areas must be accurate. (military and engineering maps)and engineering maps)

Flat Plane ProjectionsFlat Plane Projections

• Used to map areas of the North and South Used to map areas of the North and South poles. Areas near that point show little poles. Areas near that point show little distortiondistortion

• Farther away from the point the greater the Farther away from the point the greater the distortion of area, shape, and scale.distortion of area, shape, and scale.

• Shows no more that ½ of the Earth at one Shows no more that ½ of the Earth at one time.time.

• Also called Also called Azimuthal ProjectionAzimuthal Projection

Gnomonic ProjectionGnomonic Projection• Circles of latitude lines and straight longitude lines Circles of latitude lines and straight longitude lines

form a wheel-like pattern.form a wheel-like pattern.

• Especially useful to navigators because the shortest Especially useful to navigators because the shortest distance between two places on the map is found by distance between two places on the map is found by drawing a straight line between them {this line is drawing a straight line between them {this line is actually a part of a actually a part of a great circlegreat circle – any imaginary line – any imaginary line that circles Earth and divides it into 2 equal partsthat circles Earth and divides it into 2 equal parts

• Navigators use these along with true-compass Navigators use these along with true-compass direction maps to make their travel plans.direction maps to make their travel plans.

Robinson ProjectionRobinson Projection• Equal areas – shown with high degree of Equal areas – shown with high degree of

accuracyaccuracy

• Conformal except near edges of map where Conformal except near edges of map where distortion increasesdistortion increases

• Valuable for showing entire world.Valuable for showing entire world.

Goode’s InterruptedGoode’s Interrupted• High degree of accuracy in area and shapeHigh degree of accuracy in area and shape• Distorted direction and scale.Distorted direction and scale.• Valuable for showing Land masses.Valuable for showing Land masses.

Points to RememberPoints to Remember

• The projection one chooses to use depends The projection one chooses to use depends on the information one wants.on the information one wants.

• All Maps are projections – they transfer All Maps are projections – they transfer Earth’s features from the globe to a flat Earth’s features from the globe to a flat surface (map).surface (map).

• When large areas of Earth are mapped, When large areas of Earth are mapped, distortion is more serious.distortion is more serious.

• When mapping small areas like cities, When mapping small areas like cities, distortion is not usually evident.distortion is not usually evident.