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Maps

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  • S.D. HAMPTON-COLE CRAWFORD COLLEGE LONEHILL
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    • 1. MMMMMMMaps areaMMMMMMMazing CRAWFORD COLLEGE LONEHILL 1 GEOGRAPHY
    • 2. AS LONG ASPEOPLE HAVEBEEN LITERATE,THEY HAVEUSED MAPS. CRAWFORD COLLEGE LONEHILL 2 GEOGRAPHY
    • 3. MAPS HAVE BEEN USEDFOR CENTURIES AS ARECORD OF KNOWLEDGEAND AS A MEANS TOEXPRESS THATKNOWLEDGE CRAWFORD COLLEGE LONEHILL 3 GEOGRAPHY
    • 4. CRAWFORD COLLEGE LONEHILL 4 GEOGRAPHY
    • 5. CRAWFORD COLLEGE LONEHILL 5 GEOGRAPHY
    • 6. CRAWFORD COLLEGE LONEHILL 6 GEOGRAPHY
    • 7. CRAWFORD COLLEGE LONEHILL 7 GEOGRAPHY
    • 8. CRAWFORD COLLEGE LONEHILL 8 GEOGRAPHY
    • 9. TODAY, MORETHAN EVERBEFORE, PEOPLEARE USING MAPS. THEY USE MAPS TO EXPRESS, ANALYSE AND UNDERSTAND KNOWLEDGE AND INFORMATION CRAWFORD COLLEGE LONEHILL 9 GEOGRAPHY
    • 10. ALMOST EVERY GRAPH, TABLE OR OTHER GRAPHICAL REPRESENTATION CAN BE BETTER REPRESENTED WITH A CUSTOMISEDUSING MAPS WE MAP.CAN VISUALISERELATIONSHIPSAND CONNECTIONSBETWEEN THINGSIN A WAY WECANNOT DO WITHANYTHING ELSE. CRAWFORD COLLEGE LONEHILL 10 GEOGRAPHY
    • 11. CRAWFORD COLLEGE LONEHILL 11 GEOGRAPHY
    • 12. THERE IS A MAP FOR ALMOSTANYTHING YOU CAN THINK OFAND THEY ARE GENERALLYARRANGED INTO THREECATEGORIES: CRAWFORD COLLEGE LONEHILL 12 GEOGRAPHY
    • 13. POLITICAL MAPS CRAWFORD COLLEGE LONEHILL 13 GEOGRAPHY
    • 14. Topographical maps These show physical andhuman features of the land.Includes natural landscapefeatures like coastlines,mountains, rivers, forest etcand features associatedwith human activity likedams, agriculture, cities,roads, railway lines etc.Special map symbols areused to represent thesefeatures.Small land surfaces areshown in great detail. CRAWFORD COLLEGE LONEHILL 14 GEOGRAPHY
    • 15. Thematic Maps…CRAWFORD COLLEGE LONEHILL 15 GEOGRAPHY
    • 16. CRAWFORD COLLEGE LONEHILL 16 GEOGRAPHY
    • 17. What is a map?A map is a reduced, generalised, symbolicrepresentation of a curved portion of theearths surface on a piece of paper.All maps must have: • a scale • direction of True North • a key with the symbols used. Maps are constructed from aerial photographs. CRAWFORD COLLEGE LONEHILL 17 GEOGRAPHY
    • 18. CRAWFORD COLLEGE LONEHILL 18 GEOGRAPHY
    • 19. WHAT DIFFERENT THINGS DOWE FIND ON AND AROUND ATOPOGRAPHICAL MAP? CRAWFORD COLLEGE LONEHILL 19 GEOGRAPHY
    • 20. RATIOAND AME E SCALE LONGIT S COD MARKI NMA P UD E NG MARKINGS LATITUDE MAN MADE FEATURES NATURAL FEATURES CONTOUR LINES KEY CRAWFORD COLLEGE LONEHILL 20 GEOGRAPHY
    • 21. NORTH LINE SCALEARROW ANDDECLINATION INFO CONTOUR INTERVAL PUBLICATION PROJECTION MAP-CODE DETAILS AND INFO GRID DATE N IO JE CT P RO GRID CRAWFORD COLLEGE LONEHILL 21 GEOGRAPHY
    • 22. PS: A TRIG BEACON (IN CASE YOU’VE EVER WONDERED)CRAWFORD COLLEGE LONEHILL 22 GEOGRAPHY
    • 23. Oblique photographsThese are taken from an aeroplane or high point at an angle.They can tell the viewer a great deal about the nature of features, particularlyheights but are only of limited use to the cartographer because decreasing scalefrom foreground to background makes measurements of distances almostimpossible.Advantages:Disadvantages:If the horizon is visible, the photograph is called a ................. oblique photograph- it is taken at an angle of between 60° to 90° from the horizon.A .................... oblique does not show the horizon and is taken at an angle of .........°. CRAWFORD COLLEGE LONEHILL 23 GEOGRAPHY
    • 24. CRAWFORD COLLEGE LONEHILL 24 GEOGRAPHY
    • 25. High angle Low angleCRAWFORD COLLEGE LONEHILL 25 GEOGRAPHY
    • 26. Vertical Aerial photographsThese are taken from an aeroplane where the camera points down vertically i.e. a .............°anglefrom the horizon.Most objects can be seen although tall trees might hide smaller objects, no building obscuresotherbuildings.The area of buildings can be accurately judged and the layout of the roads andrailways is clearly shown.Tall trees, chimneys etc. can be recognised by their shadow.Advantages: Disadvantages:How are Vertical Aerial photographs taken? CRAWFORD COLLEGE LONEHILL 26 GEOGRAPHYCameras are installed in an aircraft which flies over an area in parallel strips taking photographs
    • 27. CRAWFORD COLLEGE LONEHILL 27 GEOGRAPHY
    • 28. Satellite PhotographsThese are the photographs of the future.Information is gathered by a satellite which hasbeen launched into space and this information issent back to earth.The type of information collected can be used toforecast weather, detect rocks which containvaluable minerals and the images canbe used to draw accurate maps of areas. CRAWFORD COLLEGE LONEHILL 28 GEOGRAPHY
    • 29. CRAWFORD COLLEGE LONEHILL 29 GEOGRAPHY
    • 30. CRAWFORD COLLEGE LONEHILL 30 GEOGRAPHY
    • 31. Orthophoto maps These are a combination of vertical aerial photographs and topographic maps.The scale of an orthophoto map is 1: 10 000, which means that they are largescale, and show a close-up, detailed view.Advantages: • They combine the advantages of vertical aerial photographs with maps. CRAWFORD COLLEGE LONEHILL 31 GEOGRAPHY
    • 32. Contour lines, trig beacons, benchPlace names marks and spot height CRAWFORD COLLEGE LONEHILL 32 GEOGRAPHY
    • 33. CRAWFORD COLLEGE LONEHILL 33 GEOGRAPHY
    • 34. They can also be used with maps to provide more detailCRAWFORD COLLEGE LONEHILL 34 GEOGRAPHY
    • 35. Photo scale = (PD /MD) x MS CRAWFORD COLLEGE LONEHILL 35 GEOGRAPHY
    • 36. There are THREE types of map based on scale:Small-scale Maps (Smaller than 1: 5 000 000)•These are used to show patterns of continental and world extent e.g.distribution of land and water surfaces, railways of Africa etc.•These maps are generalised i.e. main roads, rivers, large towns and cities.•A world map or map of Southern Africa is a small-scale map.Medium-scale Maps (Between 1: 5 000 000 to 1: 500 000)•These maps are used for data on a national and regional basis.•Roads, maps of drainage systems and administrative boundaries are shown.•A map of South Africa showing the provinces, towns and transport networks isan example of a medium-scale map.Large-scale Maps (Larger than 1: 500 000)•These maps give detailed information.•Land forms, agricultural land use, streets in towns and distribution of farmsshown.•These include the 1: 50 000 topographical maps and 1: 10 000 orthophotomaps used by geographers. CRAWFORD COLLEGE LONEHILL 36 GEOGRAPHY
    • 37. CRAWFORD COLLEGE LONEHILL 37 GEOGRAPHY
    • 38. Using Map Scales•A map scale is the relationship between a distance depicted on a map and the corresponding distance in reality (on theground.)•There are THREE types of scales:Numerical Scales•These are representative fractions or ratios e.g. 1: 50 000•This means that 1 unit on the map represents 50 000 of the same units on the ground.Verbal or Word Scales•A comparison is made e.g. mm to km cm to m.• EXAMPLE1: 50 0001 mm on the map represents 50 000 mm on the groundKHDMd cm0 0 5 0,0 0 0therefore 1 mm on the map represents 50 m on the ground.1 cm on the map represents 0,25 km on the ground.KHDMdcm•2 5 0 0 0, 0therefore 1 cm on the map represents 25 000 cm on the ground.Numerical ratio is 1: 25 000.Linear Scales•This is a horizontal straight line on which distances are shown in terms of their equivalent on the map.•They are useful to measure the approximate distance between points. CRAWFORD COLLEGE LONEHILL 38 GEOGRAPHY
    • 39. CALCULATING STRAIGHT LINE AND WINDING DISTANCES Formula: MAP DISTANCE SCALE Method: Find the distance on the map in centimetres. If it’s a winding distance, use a piece of string, a piece of paper, or dividers to measure the distance (see diagrams A and B.) Use a ruler to measure straight lines. Example: MD = 25 cm 1: 50 000 SHORTCUTS ? SCALE = 1: 50 000 (Calculate the distance in Kilometers) = 25 cm x 0,5 km (MD x SCALE) = 12, 5 km CRAWFORD COLLEGE LONEHILL 39 GEOGRAPHY
    • 40. CALCULATING AREAFormula: (LENGTH SCALE) (BREADTH SCALE) or, (L S) (B S)Example: Work out the area of A.A = (L x S) (B x S)= (8 x 0,5 km) (4 x 0,5 km)= (4 km) (2 km) 8 cm= 8 km2 4 A cm ( Scale = 1: 50 000 )  CRAWFORD COLLEGE LONEHILL 40 GEOGRAPHY
    • 41. CRAWFORD COLLEGE LONEHILL 41 GEOGRAPHY
    • 42. Direction This indicated by the points on a compass e.g. North, South, North-east etc.CRAWFORD COLLEGE LONEHILL 42 GEOGRAPHY
    • 43. REMEMBERTO STARTAT ‘FROM’POINT CRAWFORD COLLEGE LONEHILL 43 GEOGRAPHY
    • 44. True Bearings True and Magnetic bearings A true, geographic or •A true bearing is measured in degrees from true north in a clockwise direction.azimuthal bearing is •To measure true north, the points must be joined with a straight line.represented by an angle •A vertical line is then drawn through the point from which the bearing is to be measured.measured with a protractor. •This line represents true north and is drawn parallel to the lines of longitude. •The protractor is placed with 0/360° at the top and 180° at the bottom.Method: •The measurement is read clockwise from true north to the line joining the two points. Join up the two pointswith a straight line. Draw a perpendicularline through each of the points,parallel to the lines oflongitude. Measure the bearingwith a protractor at the pointwhere the questions readsFROM. Measure CLOCKWISEfrom the perpendicular line(True North) to the line joiningthe two points. 0/360° on the protractorshould be at the top. Read thebearing on the outer ring of the protractor. The answer will be indegrees(°) CRAWFORD COLLEGE LONEHILL 44 GEOGRAPHY
    • 45. 180 = 200 + 20CRAWFORD COLLEGE LONEHILL 45 GEOGRAPHY
    • 46. •A magnetic bearing is read from a magnetic compass and includes the true bearing andthe magnetic declination.•This is because a compass needle always points to Magnetic North, and not thegeographic North Pole (True North).•The earth is like a big magnet with one pole in the Arctic region and the other pole in theAntarctic region.•These magnetic poles change their positions very slowly.•The angle between the direction in which the compass needle points and True Northis known as the magnetic declination.•This is measured in degrees East or West of True North, and depends on the position ofthe point in relation to the True and Magnetic North. Refer to the diagram below. CRAWFORD COLLEGE LONEHILL 46 GEOGRAPHY
    • 47. 3) POSITION (LATITUDE AND LONGITUDE)Co-ordinates are used to locate features on a map. They consistof a LATITUDE and a LONGITUDE reading. Lines of latitude andlines of longitude are imaginary lines running from east to westand north to south respectively. Where any lines of latitude andlongitude intersect, a co-ordinate is read.Latitude readings are given as either north or south (of theEquator), and lines of longitude are given as either east or west(of the Greenwich Meridian).Co-ordinates always have the latitude reading first, and thelongitude reading last.The distance between lines of latitude are always 37mm, but thedistance between the lines of longitude might vary. CRAWFORD COLLEGE LONEHILL 47 GEOGRAPHY
    • 48. How are co-ordinates used to fix positions?The absolute location of any point on the Earths surface can be indicated byusing geographical co-ordinates.Geographical co-ordinates refer to the lines of latitude and longitude.A line of latitude is an imaginary circle running around the globe parallel to theequator.Degrees of latitude are the angular distance measured at the centre of the earth.Lines of latitude are also called parallels.There are 180° of latitude.The equator at 0° is the most important.A line of longitude is an imaginary line joining the North and South poles.A degree of longitude is the angular distance measured at the centre of theearth.Lines of longitude are also called meridians.There are 180° of longitude - 0° or Greenwich meridian is the most important.The degree of Latitude is given first, followed by the degree of longitude – readDOWN first and then RIGHT.Each degree of latitude and longitude is divided into 60 minutes () and each CRAWFORD COLLEGE LONEHILL 48 GEOGRAPHYminute into 10 units or 30 seconds (“). Please note that seconds are not
    • 49. DOWN, THEN RIGHT 1 MINUTE OF10 DECIMALS 19°18’, 3 EAST LATITUDEIN EACHMINUTE 33°45’, 8 SOUTH CRAWFORD COLLEGE LONEHILL 49 GEOGRAPHY
    • 50. CRAWFORD COLLEGE LONEHILL 50 GEOGRAPHY
    • 51. How are 1:10 000 Orthophoto map referencedifferent?An orthophoto map with a larger scale of 1:10 000 covers asmaller area than a topographical map.One topographical map sheet contains 25 orthophoto mapsheets.E.g.: 2334 AD 12 CRAWFORD COLLEGE LONEHILL 51 GEOGRAPHY
    • 52. THE THIRDDIMENSION CRAWFORD COLLEGE LONEHILL 52 GEOGRAPHY
    • 53. CRAWFORD COLLEGE LONEHILL 53 GEOGRAPHY
    • 54. CRAWFORD COLLEGE LONEHILL 54 GEOGRAPHY
    • 55. LANDFORMS SP URVA V L LE Y CRAWFORD COLLEGE LONEHILL 55 GEOGRAPHY
    • 56. LANDFORMS TERRACED SLOPE SP UR VA V L LE Y POORT / GAP SADDLECONCAVE GENTLE CONVEX STEEP CRAWFORD COLLEGE LONEHILL 56 GEOGRAPHY
    • 57. The Spacing of Contour Lines: Different Slope TypesConcave SlopesThe lines are far apart at the bottom of the slope (gentle), but close together at thetop (steep). It forms a hollowed out shape in a cross-section.Convex SlopesThe opposite to a concave slope. The lines are far apart at the top of the slope( gentle) and close together at the bottom (steep). The slope forms a bulge in cross-section.Terraced or Stepped SlopesThe contour lines are alternatively spaced far apart and close together. Theseslopes are common in the Karoo and Free State where different layers of hard andsoft rock produce a stepped slope.CliffsThe contour lines touch or are very close together producing a vertical or nearvertical rise of land. CRAWFORD COLLEGE LONEHILL 57 GEOGRAPHY
    • 58. How are landforms recognised by contour patterns?Valleys and Spurs Contour lines both form a "V" shape - in a valley the point of the "V" faces upstream, and a valleyoften contains a river. The point of the "V" in a spur faces downhill. A spur is a ridge from a range of hills or mountains. They often have convex slopes and occur between two valleys. They form local watersheds and direct rainfall into the surrounding valleys. They never contain a river.GorgeA deeply incised river valley - it is very narrow with steep sides e.g. Oribi Gorge.Waterfalls These occur in a river valley where the contour lines touch to form a cliff. The water flows over the cliff producing a waterfall e.g. Howick Falls.Watershed or Divide The boundary between drainage areas is called the watershed. It is drawn as a dotted line along the high points and crests of spurs. A watershed normally bisects spurs and high points e.g. hills, mountain ridges etc. It separates water flowing in opposite directions e.g. The Witwatersrand. CRAWFORD COLLEGE LONEHILL 58 GEOGRAPHY
    • 59. CRAWFORD COLLEGE LONEHILL 59 GEOGRAPHY
    • 60. Scarp and Dip slope A scarp is an area where the contour lines are close together producing a steep rise (Cliff). The large form of this feature is called an Escarpment A Dip slope often occurs in conjunction with a scarp slope. It is a gentle slope that slopes away from the top of the scarp.Saddle A gentle dip that occurs between two hilltops or mountain peaks. It is seldom more than two contours in depth.Pass or Neck A large dip in a range of hills or mountains. It is at a higher elevation than the surrounding plain. It often contains roads or railway lines. A "V" shape can be seen increasing in altitude jutting out from either side of the pass e.g. Van Reenens Pass.Poort or Gap A river cuts through a range of hills or mountains. This forms a break in the range at the same elevation as the surrounding plain. Roads and railway lines also go through poorts. The contour lines do not form a "V" shape in the poort e.g. Hartebeespoort in the Magaliesberg and MeiringsPoort in the Swartberg. CRAWFORD COLLEGE LONEHILL 60 GEOGRAPHY
    • 61. What is Gradient and how is it calculated?The slope of the land is called the GRADIENT.In South Africa, main railway lines have a gradient of less than 1: 50 with a maximum of 1: 66. National roads have gradients ofapproximately 1: 20A 1:1 gradient is very steep and can only be climbed by using feet and hands.Formula: Gradient = Rise or Vertical distance or Difference in height Run Horizontal distance Distance on ground CRAWFORD COLLEGE LONEHILL 61 GEOGRAPHY
    • 62. CROSS-SECTIONS Study Mark-off Infer / deduce Graph LabelCRAWFORD COLLEGE LONEHILL 62 GEOGRAPHY
    • 63. VERTICALEXAGGERATION CRAWFORD COLLEGE LONEHILL 63 GEOGRAPHY
    • 64. How is the vertical exaggeration of a cross-section worked out? All cross-sections are drawn to a particular vertical scale and if we change the scale, we can also change the appearance of the cross-section. Formula  V.E= VS or Vertical Scale HS Horizontal Scale   Method Write down the formula. Substitute the information given to you into the formula. Change the VS from a word scale to a numerical scale (a ratio). Write both ratios as representative fractions. Invert the bottom fraction and multiply out. Divide the numerator (top number) by the denominator (bottom number) The answer will be x timesCRAWFORD COLLEGE LONEHILL 64 GEOGRAPHY
    • 65. What do we mean by inter-visibility? This is to determine whether one pointcan be seen from another point on thecross-section. Once the cross-section is drawn, jointhe two points you are trying toestablish the intervisibility of with a line. If there is no obstruction, there isintervisibility between the two points. If there is topography obstructing theline of sight, then there is nointervisibility CRAWFORD COLLEGE LONEHILL 65 GEOGRAPHY
    • 66. INTERPRETING MAPSCONSIDER THE FOLLOWING SENTENCE:A turgle swashed a brad while it snorped an urple troxle.You should be able to READ this sentence quite easily, even though you may have no ideawhat it means. You can even ANALYSE it relatively easily. For example, you can count thewords, or the words with four letters or more…you should even be able to work out whichare the nouns and verbs. INTERPRETING the sentence though, requires a little more. In interpreting anything, including the strange sentence above, it is important that you find MEANING and valuable conclusions about what you are analyzing. But to do this, you need EVIDENCE. You simply do not have enough evidence to interpret the exampleIf someone told you that ‘troxles’ are plants. What would brads be?It is important, when you try to interpret anything that you LOOK FOR EVIDENCE FIRST!This is especially true when interpreting maps. CRAWFORD COLLEGE LONEHILL 66 GEOGRAPHY
    • 67. MAPPROJECTIONS CRAWFORD COLLEGE LONEHILL 67 GEOGRAPHY
    • 68.    What is a Map Projection?  Map projections are a system for transferring the surface of the spherical Earth to a flatarea. In order to do this the continuity of the map is broken e.g. the globe gores mapand/or certain spherical properties are sacrificed, creating deformation and/or distortionin:•Direction and bearing•Shape/angles at different points•Area•Distances•No map can accurately show all these factors, so depending on the purpose of the map, certainfactors are more or less important and therefore the projection chosen depends on the purposefor which the map will be used e.g. for a pilot or sailor, direction and scale must be accurate.•Different projections keep one or more properties true. CRAWFORD COLLEGE LONEHILL 68 GEOGRAPHY
    • 69. A map projection is an orderly system of lines of latitude (parallels) and lines of longitude (meridians) used as a basis for drawing a map on a flat surface.   •Azimuthal projections show correct direction/bearing relationships •Conformal projections are true in terms of shape/form for small areas •Equal-area projections show correct area relationships •Maps that correctly show the  distance between points are often CRAWFORD COLLEGE LONEHILL called equidistant maps (note that  69 GEOGRAPHY the shortest distance between two 
    • 70. Equal area projections preserve area, and are also called equivalent projections. Most thematic maps should use an equal area projection.  Conformal projections preserve angles, and are useful for navigational charts and weather maps. Lines of latitude and longitude Azimuthal projections preserve intersect at right angles. Shape is direction from one point to all other preserved for small areas, but the points. This property can be shape of a large area such as a combined with any of the other continent will be distorted three. Thus, it is possible to have an significantly. Conformality is an equal area azimuthal projection, extremely valuable property for maps such as a Lambert Azimuthal Equal that are to be used critically, and not Area projection or an Azimuthal just for general orientation or Equidistant projection. decoration. A common conformal   projection is the Lambert Conformal Compromise projections attempt to Conic projection. minimize overall distortion, but  preserve none of the four properties. Equidistant projections preserve The Robinson projection, for distances, but no projection can example, is neither equal area nor preserve distances from all points to conformal, but is aesthetically all other points. pleasing and suitable for general mapping. CRAWFORD COLLEGE LONEHILL 70 GEOGRAPHY
    • 71. The 3 basic types of map projections are: 1.Cylindrical 2.Conical 3.AzimuthalCRAWFORD COLLEGE LONEHILL 71 GEOGRAPHY
    • 72. Azimuthal Conical Cylindrical CRAWFORD COLLEGE LONEHILL 72 GEOGRAPHY
    • 73. • Mathematical calculations are used toIn Grade 11 you project lines of latitude and longitude onto a cylinder – visualize a paperstudy Mercator’s cylinder wrapped around the globe with a light inside the cylindercylindrical projecting the graticule (lines ofprojection. This • latitude and longitude) on it. Parallels and meridians are straightprojection has • lines and are parallel to one another. Lines of latitude and longitude crossequality of linear each other at right angles. • Distances between parallels becomescale and greater toward the poles intherefore shows proportion to the distance between meridians.correct distancerelationships.  CRAWFORD COLLEGE LONEHILL 73 GEOGRAPHY
    • 74. The Mercator projection shows courses of constantbearing as straight lines. While common, scholarsadvise against using it for reference maps of theworld because it drastically inflates the highlatitudes. 10000 CRAWFORD COLLEGE LONEHILL 0 10000 20000 Miles 74 GEOGRAPHY
    • 75. CRAWFORD COLLEGE LONEHILL 75 GEOGRAPHY
    • 76. CRAWFORD COLLEGE LONEHILL 76 GEOGRAPHY
    • 77. CRAWFORD COLLEGE LONEHILL 77 GEOGRAPHY
    • 78. CRAWFORD COLLEGE LONEHILL 78 GEOGRAPHY
    • 79. CRAWFORD COLLEGE LONEHILL 79 GEOGRAPHY
    • 80. What is GIS?It is a new tool that is used to make geography morerelevant.It is a computer system that links geographic information(where things are) with descriptive information about thoseplaces (what thing are like)This info is used to produce new maps.The user selects what is required from many layers ofdifferent informatione.g. a map with roads, vegetation, where people live, rainfallamounts, peoples income, pollution etc.Geographic information is basic to biology, geology,environmental science, sociology, politics and economicsThe world’s problems exist in a geographic context andinformation can be used to predict, monitor and solve theseproblems. CRAWFORD COLLEGE LONEHILL 80 GEOGRAPHY
    • 81. TerminologyEntity: A real world feature that can’t be subdivided e.g. a tree, house, river etc.Attribute: A quality or characteristic.Object: A point or set of points used to represent a real world entity.There are three types of objects:Point: A GIS object that represents a geographical feature that is too small to show as a line orarea on a small scale map e.g. lamp post or post box. These are defined by their co-ordinates.• PointLine: A set of ordered co-ordinates that represent a narrow one-dimensional geographicalfeature such as a stream or road. The beginning and end points called nodes.• • (node) • • • Line Curved Line Directed Line Intersecting LineArea: A two-dimensional object such as a recreational area or dam. The boundaries of thearea are defined by a closed set of lines called a polygon. CRAWFORD COLLEGE LONEHILL 81 GEOGRAPHY
    • 82. CRAWFORD COLLEGE LONEHILL 82 GEOGRAPHY
    • 83. TerminologyVECTOR DATA: POINTS AND LINESRASTER DATA: ‘PIXEL’ OR SHADED DATA (SCANNED MAPS AND PHOTOS)DATA MANAGEMENTStorage requirements, cross-referencing, analysing and ease ofaccess (vector data often preferred). CRAWFORD COLLEGE LONEHILL 83 GEOGRAPHY
    • 84. CRAWFORD COLLEGE LONEHILL 84 GEOGRAPHY
    • 85. INFORMATION IS ACQUIREDVIA REMOTE SENSING, GEO-REFERENCED TABULARDATA AND FIELDWORK CRAWFORD COLLEGE LONEHILL 85 GEOGRAPHY
    • 86. CRAWFORD COLLEGE LONEHILL 86 GEOGRAPHY
    • 87. CRAWFORD COLLEGE LONEHILL 87 GEOGRAPHY
    • 88. CRAWFORD COLLEGE LONEHILL 88 GEOGRAPHY
    • 89. CRAWFORD COLLEGE LONEHILL 89 GEOGRAPHY
    • 90. MMMMMMMaps TRULY areaMMMMMMMazing CRAWFORD COLLEGE LONEHILL 90 GEOGRAPHY

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