Anybody who believes that the way to a mans heart is through his stomach flunked geography. Robert Byrne

Coordinate Systems Thetermcoordinatesystemasdefinedingeometryisasysteminwhichapositionofapointoranobjectcanbedeterminedbymeansofnumericalvalueswhichmaybeasinglenumberoragroupofnumbers.InGeographicInformationSystem(GIS)ausershouldbefamiliarwiththetypeofcoordinatesystemusedinamap.Beingknowledgeablewiththecoordinatesystem,theuserwillbeabletomeasureaccuratelydistancesofobjectsonthemap.

TwotypesofcoordinatesystemsinGIS

TherearetwotypesofcoordinatesystemsthataGISusermustconsider.ThesecoordinatesystemsaretheGeographicCoordinateSystem(GCS)andtheProjectedGeographicSystem(PCS).Choiceofthecoordinatesystemswilldependonthepurposeandobjective.

GeographicCoordinateSystem(GCS)definesthelocationofanobjectonaspherical(orspheroidal)modeloftheearth.Figure21showstheGCS.

Figure 2-1

GCSrepresentslocationontheearthsurfacebysetsofnumbersand/orletters.Oneofthenumbersrepresentstheverticalposition,andtheotherwillbethehorizontalposition.Commonly,thesearelatitude,longitude,andelevation.Latitudeistheanglebetweentheequatorialplaneandahorizontallinethattraversethroughaspecifiedobject.Equatorisanimaginarylinethatdividesthenorthernhemispherefromthesouthernhemisphere.ImagineavertexofananglelocatedattheverycoreoftheglobeandoneofitsraysisattheequatorandastheotherraymovestowardtheNorthPole,theangleofthevertexalsoincreasesuntilitreaches900.ThisisalsowhathappenedwiththerayasitmovestowardtheSouthPole.Thus,theequatorhasthelatitudeof00,theNorthPole900N,andtheSouthPole900S.

Longitudeontheotherhandistheeastwestlocationofanobjectonthesphericalmodel.Thedivisionbetweentherightandtheleftsideoftheglobeiscalledthemeridian.Animaginaryreferencelineisactuallyestablishedin1851bySirGeorgeAiryanditiscalledthePrimeMeridian.Thisisalinethatpassesthrough

Greenwich,UKandtheinternationalzerolongitudereferenceline.Movingeastward,thePrimeMeridianisfrom00to+1800(00to1800E).Goingwestward,itisfrom00to1800(00to1800W).Asingledegreeintervalforeitherthelatitudeorlongitudeisapproximatelyequalto111kilometers.ExamplesofcoordinatesgiveninGCSare1005122.3N12503215.6EorN1005122.3E12503215.6.

ProjectedCoordinateSystem(PCS)representsthelocationofanobjectonaflatmodeloftheearth(map).AnexampleofaPCSisshowninFigure22.

Figure 2-2

PCSisasystematicwayoftransformingthesphericalglobeintoaflatplane.Sincetherearedifferentmethodsapplied,PCSvaries.Figure23showsdifferentprojectionsofSouthAmerica.

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ProjectionsonaProgrammaticLevel

Eachdifferentprojectionisamathematicalfunctionthattakesthepairedcoordinatesasinputs[(x,y)],andgeneratestheoutputpairofcoordinatesas[f(x,y)](considerTable21).

Input Output Angles Cartesian

coordinates State Plane UTM

Miller Cylindrical Lambert Azimuthal

Table 2-1

AnexampleofhowacertainprojectionchangesasetofcoordinatesisshowninTable22.

Projection, Zone, Datum (units) X Y geographic, NAD27 (decimal degrees) -122.350 47.620

UTM, Zone 10, NAD25 (meters) 548843.5049 5274052.0957 State Plane, WA-N, NAD83 (feet) 1266092.5471 229783.3093

Table 2-2

Geographiccoordinatesareconvertedfromangularunits(degrees)todistanceunitsonamap(feetormeters).

ShapeoftheEarth

IfyouthinkthatEarthisaperfectsphere,thenyouaresurelyatalostthatisbecausetheearthasmostpeoplethoughtassmoothlysphericalisactuallyjagged.Ifyouremoveallbodiesofwaterfromthesurfaceoftheearth,thetrueshapeoftheearthwillberevealedtoyou(seeFigure27).

Figure 2-7

Theearthisspheroidalorellipsoid,itisnotperfectlysymmetrical.InFigure28,thesemimajor(bluelines)andthesemiminor(redlines)axisgeographicallywillnotcoincide.

Figure 2-8

Ithasbeenrevealedthroughsatellitedataandobservationsoftheexistenceofseveralellipticaldeviations.OneexampleisthefactthattheSouthPoleismuchclosertotheequatorthantheNorthPole.Anotherfactisthattheearthsspheroiddeviatesslightlyfordifferentregionsoftheearth.Toaddressthesedeviations,differentspheroidsareusedthroughouttheworld.But,allowingdeviationstobeignoredandusingthesamespheroidforanylocationsontheearthcouldleadtoerrorsofseveralmeters,orevenhundredofmeterswhenappliedonaregionalscale.

Clarke1866spheroidwasthemostcommonlyusedspheroidforNorthAmericainmostgeographicdatabases,butitwasreplacedtodaywithGRS80spheroid(seeFigure29aandFigure210bforcomparison).

Figure 2-9a (GRS80) Figure 2-9b (Clarke 1866)

GRS80wasactuallycreatedusingsatelliteinformation,anditisnowbeginningtoreplacethetraditionalgroundmeasuredspheroids,suchasClarke1866.(Note:Bothspheroidsmeasurementsareroundedtothenearestmeter).

Datum

Geoidistheapproximationfortheshapeoftheearthatsealevel.InFigure210,observehowtheellipsoid/spheroidfitsonthemodel.Knowingwhatspheroidisused;applyingadatumwilldefinethefitforaparticularspheroid.Theellipsoid/spheroidmusthaveazeropointsomewhereandthemeansealevelmustbeestablishedfromthegeoid.

Figure 2-10

Anobjectscoordinatevaluesvarywiththespheroidandthedatum.OnFigure211,theredcoloredaxisisthelocaldatumcoordinatesystemwhichisagoodfitforlocaldata.Ontheotherhand,thebluecoloredaxisistheearthcentereddatumcoordinatesystemwhichisagoodfitforaglobalscaledata.

Figure 2-11

GISLaboratoryExercise#2CoordinateSystems

Objectives:

Inthisexercise,youwillbeabletolearnhowto:

FindtheinformationofthecoordinatesystemusingArcCatalogandArcMap. Viewandexplorerealtimeprojection. Modifythecoordinatesystemofadataframe.

Examinethecoordinatesystemofafeatureclass

StartArcMap

IftheGettingStartedwindowwillappearjustcloseitorclicktheCancelbutton.Anemptymapisdisplayed.

ClickontheCustomizemenuandthentheArcMapOptions

SelecttheMetadatatab.UndertheMetadataStylegroupbox,clickthedropdownlistandselectISO19139MetadataImplementationSpecification.BesuretochecktheAutomaticallyupdatewhenmetadataisviewedcheckbox.ClickOKtoclosetheArcMapOptionswindow.

Savetheemptymapinyour\myGISOutputsfolderasmyCoordinateSystems.

IntheCatalogwindow,rightclickFolderConnectionsandlocatetheLearnGIS2folder.HighlightLearnGIS2andclickOK.

IntheCatalogwindow,expand...\LearnGIS2(clickthe+signbesidetheLearnGIS2folder).ExpandCoordinateSystemsfolderandthenexpandWorldgeodatabase.

RightclickontheCountriesfeatureclassandclickItemDescription.

ClickthePreviewtab.

Observethatthegeographyisstretchedfromeasttowest.Canada,forexample,iswiderandmorecompressedfromnorthtosouththanyouusuallyseeit.Antarctica,ontheotherhand,seemslargerthanRussia.

OntheItemDescriptionwindow,clicktheIdentifytool.

ClicktheeasternborderofRussia.

ResizetheItemDescriptionwindowandmoveitsoyoucanseeboththeIdentifyResultswindowandthemap.

Note:ThevaluesintheLocationfieldarearrangedaslongitudelatitudeformat.Example:123.4567812.34567,hasalongitudeof123.45678andalatitudeof12.34567.

1. WhatisthevalueoflongitudespecifiedintheIdentifyResultswindow?_______________________

ClickthewesternmostborderofNorthAmerica(Alaska).

2. WhatisthevalueofthelongitudespecifiedintheIdentifyResultswindow?

_______________________

ClickthenorthernborderofGreenland.

3. WhatisthevalueofthelatitudespecifiedintheIdentifyResultswindow?_______________________

ClickonthesouthernmostareaofAntarctica.

4. WhatisthevalueofthelatitudespecifiedintheIdentifyResultswindow?_______________________

Withintheextentofthedata,thevaluesrangefrom90to90inthenorthsouthdirectionand180to180intheeastwestdirection.

ClosetheIdentifyResultswindow.

IntheItemDescriptionwindow,clicktheDescriptiontabandresizetheItemDescriptionwindowtoenlargeit.

ExpandArcGISMetadataandthenexpandESRISpatialInformationandviewtheextentinformation.

Thecoordinatevaluesareindecimaldegrees.ThevaluesthatwerespecifiedinIdentifytoolshouldbeapproximatelyclosetothesevalues.Note:thesearelatitudelongitudevaluesexpressedindecimalformratherthanindegrees,minutes,andseconds.

Ifneeded,scrolldowntothecoordinatereference.

5. Whatisthetypeandthegeographiccoordinatereferenceappliedonthismap?_______________________________________________________________________

ClosetheItemDescriptionCountrieswindow.

Examinethecoordinatesystemofanotherfeatureclass

UsingtheCatalog,previewtheContinentsfeatureclass.(Hint:RightclickContinentsandclickItemDescription.)

Thegeographylooksdifferent.Asyoucansee,thefeaturesarestretchedfromnorthtosouth,andarebentorshearedattheeastandwestedgesofthemap.

UsingtheIdentifytool,clickonalocationinthesouthernmostareaofAntarctica.

6. WhatarethevaluesofthelatitudeandlongitudespecifiedintheIdentifyResultswindow?__________________________________________________________

IdentifyalocationintheeasternmostareaofAsia.

7. WhatarethevaluesofthelatitudeandlongitudespecifiedintheIdentifyResultswindow?__________________________________________________________

IntheItemDescription,clicktheDescriptiontabandexpandArcGISMetadata.

ExpandESRISpatialInformation.

8. Whatisthetypeandthegeographiccoordinatereferenceappliedonthismap?IsthereadditionalinformationaddedtotheCoordinateReference?Whatisthisadditionalinformation?________________________________________________________________________________________________________________________________________________________________________

ClosetheItemDescriptionwindowandIdentifyResults.ClosetheIdentifywindowifnecessary.

IntheCatalogwindow,rightclicktheCanadaProvincesfeatureclassandclickProperties.

InFeatureClassProperties,clicktheXYCoordinateSystemtabandviewthecoordinatesystemproperties.

9. Fillupthenecessaryinformation:

a. Projection:_______________

b. GeographicCoordinateSystem:_______________________________

c. Datum:______________________________

d. Spheroid:_________________________

Youvedoneexploringthecoordinatesystempropertiesofthreefeatureclasses.NowletsexplorethedatainsideArcMap.

ExaminecoordinatesystemsinArcMap

DragdroptheCountriesfeatureclassintothedataframe.

Fromthetableofcontents,opentheCountrieslayerproperties(Hint:RightclickontheCountrieslayerandclickProperties).ClicktheSourcetab.

ThecoordinatesysteminformationofthelayerisdisplayedintheDataSourcearea.

ClickCancelontheLayerPropertiesdialogbox.

RightclickontheLayersinthetableofcontentstoopenthedataframesproperties.

ClicktheCoordinateSystemtab.

Thedataframealsohasacoordinatesystem,independentofitslayers.Itisshownatthetopofthedialogandalsointhecontentsofthefolder.Inthiscase,thecoordinatesystemisthesameastheCountrieslayer.Thedataframeautomaticallyadaptsthecoordinatesystemofthefirstlayerthatisaddedtoit(asshownbelow).

ClickCancelontheDataFramePropertiesdialogbox.

FromtheCatalog,dragdroptothedataframetheContinentsfeatureclass.

ObservethattheContinentsalignperfectlywiththeCountrieslayer.Whyisthisso?RecallthatthelasttimeyoupreviewedthisfeatureclassusingCatalog,themaplooksdifferently.

Again,openthedataframeproperties(Hint:RightclickonLayersandclickProperties).

Ifnecessary,clicktheCoordinateSystemtab.

InthelowerportionofthewindowjustbelowSelectacoordinatesystem:isatreeview,expandtheLayersfolder.ExpandtheContinentsfolderandtheCountriesfolder.

10. Whatisthecoordinatesystemfor:

a. Continents_______________________

b. Countries_______________________

IntheLayersfolder,youseethenativecoordinatesystemofeachlayerinthedataframe.AlthoughtheContinentslayerisinaprojectedcoordinatesystem,italignswiththenonprojectedCountrieslayer.TheCountrieslayerhasbeennonprojectedonthefly.

ClickCancelontheDataFramePropertiesdialogbox.

FromtheInsertmenu,chooseDataFrame.

Anew,emptydataframe(calledNewDataFrame)isaddedtothemapandhasautomaticallybeenactivated.

CopyandpastetheContinentslayerfromtheLayersdataframeintothenewdataframe(Hint:Rightclickthelayerinthetableofcontents,chooseCopy,thenrightclickonthenewdataframeandclickPasteLayer(s)).

Youcanseethatinthenewdataframe,thedatalooksthewayitdidintheCatalog.

OpenthepropertiesofthenewdataframeandclickontheCoordinateSystemtab.

ThisdataframeassumedtheprojectedcoordinatesystemoftheContinentslayer,whichisbasedontheEckertVIprojection.

ClickCancelontheDataFramePropertiesdialogbox.

CopyandpastetheCountrieslayerfromtheLayersdataframetothenewdataframe.

ThistimetheCountrieslayernowalignitselftotheEckertVIcoordinatesystem.TheCountrieslayerhasbeennonprojectedonthefly.

FromtheWorldgeodatabase,dragdropMajorCitiesandWorldBackgroundtothenewdataframe.

Clickinsidesomewhitespaceinthetableofcontentstodeselectthelayersyoujustadded.

ArrangethesequenceofthelayersunderNewDataFrameinthefollowingtoptobottomorder.BesurethatyourtableofcontentsisinListByDrawingOrdermode.

o MajorCitieso Countrieso Continentso WorldBackground

Youmaysymbolizeyourmapaccordingtoyourpreferences.

11. WhatisthenativeprojectedcoordinatesystemoftheMajorCitieslayer?________________________________________________________

12. WhatisthenativegeographiccoordinatesystemoftheMajorCitieslayer?________________________________________________________

Ifthereareopeneddialogboxes,youmaycloseitnow.JustretaintheArcMapwindow.

Changethecoordinatesystemofthedataframe

OpenthepropertiesoftheNewDataFrame.Ifnecessary,clicktheCoordinateSystemtab.

IntheSelectacoordinatesystem:area,expand(clickthe+signbeside)thePredefinedfolderandthentheProjectedCoordinateSystemsfolder.

InArcInfo10,coordinatesystemsareorganizedgeographicallyforthemostpart.Tofindanappropriatecoordinatesystemforworlddata,youlookintheWorldfolder;tofindoneforacontinent,youlookintheContinentalfolder;andsoon.

ExpandtheWorldfolderandscrollthroughthelistofprojectedcoordinatesystems.

MovetheDataFramePropertiesdialogboxtoacornerofthescreensoitdoesnotblockthemapdisplay.

ClickonanyofthecoordinatesystemlistedintheWorldfolderandclickApply.

Themapredrawsinthenewcoordinatesystem.Alllayersinthedataframehavebeenprojected(orreprojected)onthefly.ThenameoftheselectedcoordinatesystemappearsintheCurrentcoordinatesystem:areaoftheDataFramePropertiesdialogbox.

IntheDataFramePropertiesdialogbox,locateandselecttheRobinson(world)coordinatesystemandclickApply.

ClickCancelontheDataFrameProperties.

Inthissection,youwillobservewhatwillhappenifyouaddalayerthathasadifferentgeographiccoordinatesystemfromthedataframe.

For the following action, do not drag the CanadaProvinces to your map.

OntheStandardtoolbar,clicktheAddDatabutton ,thenaddCanadaProvincesfrom..\LearnGIS2\CoordinateSystems\Worldgeodatabase.

AsyouaddtheCanadaProvincesfeatureclasstoyourdataframe,awarningdialogboxappears(asshownbelow).

Thiswarningwillappearwheneveryouaregoingtomixdifferentgeographiccoordinatesystemstoadataframe.Theprocessoftheontheflyprojectiondoesnotautomaticallyfixthedifferencesofgeographiccoordinatesystemsofindividualfeatureclass.Inordertofixthisdilemma,anoperationcalledgeographictransformationhastobedone.

ClickClose.

ObservethattheCanadaProvinceslayerseemstofitinonourNewDataFrame.Howimportantisgeographictransformation?Atsmallscales,thedifferencesbetweentwoormoregeographiccoordinatesystemsmaynotbenoticeable.Consideringacertainpointonthedataframe,thedifferencesarejustwithinafewmeters,orperhapstensofmeters.Whetherthatwouldbesignificantwilldependonyourpurpose.

Savethemap.

Workingwithanunknowncoordinatesystem

Everyspatialdatasethasacoordinatesystem.ArcMapisabletoaligndatasetsthathavedifferentcoordinatesystemsbyprojectingonesystemontheflytomatchtheother.Occasionally,ArcMapcannotidentifythecoordinatesystemofadataset.Itisabletoaddsuchunknowndatatoamapdocumentbutcannotprojectitontheflytoalignitwithotherdata.

FromtheArcMapFilemenu,openCanada.mxdfrom..\LearnGIS2\CoordinateSystemsfolder.

Savechangestoyourmap.

13. Writedownthecoordinatesystemofthedataframe(boththegeographicalandprojectedsystems)anditslinearunitofmeasurement.______________________________________________________________________

Closethedataframeproperties.

Saveyourmapon\myGISOutputsfolderasmyCanadaCoordSys.

OntheStandardtoolbar,clicktheAddDatabutton andnavigateto\LearnGIS2\CoordinateSystemsfolder.AddthefeatureclasscalledCanadaMountains.shp.

ClickOKontheUnknownSpatialReferencewarning,ifnecessary.

Inthetableofcontents,rightclicktheCanadaMountainslayerandclickZoomToLayer.

Measuretheeastwestdistanceofthemountainfeaturesinmeters.Hint:OntheToolstoolbar,clicktheMeasuretool .Toendyourmeasurements,justpressEsc.

14. Whatisthedistance?___________________________________

ClosetheMeasuretool.

Obviously,itisimpossibleforsomanymountainstobecloselylocated.

Inthescalebox,replacethecurrentvaluewith15,000,000(refertothefollowingimage).

Ifnecessary,adjustthescaletogetaresultsimilartothefollowingimage.

OntheToolstoolbar,clickGoToXYtool .

OntheGotoXYdialogbox,clicktheUnitsbutton andchooseMeters.

Type0astheXand0astheYvalue.

The0,0pointwillshowyoutheoriginofthedataframescoordinatesystemthepointrelativetowhichallcoordinatevaluesaremeasured.

OntheGoToXYdialogbox,clicktheAddLabeledPointbutton .

Changethemapscaleto5,000.

BesurethatyouwillseetheoriginandthepointsofeveryCanadaMountainsfeatures.

ClosetheGoToXYdialogbox.

ClicktheEditmenuandchooseSelectAllElements.

PressDelete.(Thiswilldeletethecoordinatesystemorigin.)

ZoomtotheCanadabookmark(Hint:ClickBookmarksmenuandthenCanada).

ClicktheGeoprocessingmenuthenclickGeoprocessingOptions.UndertheGeneralgroupboxmakesurethattheOverwritetheoutputsofgeoprocessingoperationsischecked.UndertheBackgroundProcessinguncheckEnable,thenclickOKtoclosethedialogbox.

BesurethattheSearchdockablewindowcanbeseenattherightsideoftheArcMapwindowasshownbelow.Ifincaseitisnotvisible,justclickWindowsandthenSearch.

ClickSearch.

IntheSearchwindow,clicktheToolstextlinkthentypeonthesearchboxDefineProjection.

ClickontheDefineProjection(DataManagement)textlinktoopenthetool.Refertothefollowingimageforconfirmation.

ClicktheShowHelpbuttonifnecessary.

15. Whatistheuseofthistool?____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

ClicktheInputDatasetorFeatureClassdropdownarrowandselectCanadaMountains.

ClicktheSpatialReferencePropertiesbutton nexttotheCoordinateSystemboxtoopentheSpatialReferencePropertiesdialogbox.

ClickSelect.

IntheBrowseforCoordinateSystemdialogbox,doubleclicktheGeographicCoordinateSystemsfolder,andthendoubleclickontheNorthAmericafolder.

ScrolltotherightuntilyoucanlocateNorthAmericaDatum1983.prj.ClickittoselectitandthenclickAdd.

ClickOKontheSpatialReferencePropertiesdialogboxtoconfirmyoursettingsandcloseit.

ClickOKontheDefineProjectiontool.

WhentheprocessisCompletedyoumayclosetheprogresswindow.

ChangetheSymbologyoftheCanadaMountainslayertothemountainsymbol.Hint:ClickthesymbolrepresentingtheCanadaMountainslayerinthetableofcontents.SelectTriangle2andchangeitssizeto8points.

Saveyourwork.

DefiningCoordinateSystemtoMyPhilippinesMapLayout

FromyourExercise#1,thelastsectionthatyouveperformedistocreateaprintablemap.ThelastquestionthatwasaskedwastoexplainthereasonwhytheScaleBarandtheScaleTextwasnotabletoexpressanyaccuracy.Forthissection,wearegoingtoretrievethatexerciseandspecifyitscoordinatesystemsothatyourprintablemapwillshowtheScaleBarandtheScaleTextcontentsproperly.

OpenyourMyPhilippinesMapLayout.mxd.BesurethatyouareatLayoutView.Beforedoinganythingelse,makesurethatyourdataframeisnotatfixedscale(Hint:OpenthepropertiesofLayerdataframeandclicktheDataFrametab,underExtentselectAutomaticandclickOK).

ClicktheInsertmenuandthenclickScaleBar.IftherearealreadyexistingScaleBarandScaleText,removeit.

OntheScaleBarSelectordialogbox,chooseAlternatingScaleBar1andthenclickOK.JustclickOKontheCreatingscalebarmessagedialogbox.

Doingthesameprocedure,inserttheScaleTextbyselectingAbsoluteScale.

UsingtheLayoutZoomIn,selecttheaddedmapcomponents.

16. DescribewhatyouhaveobservedontheScaleBarandtheScaleTextofyourmap.____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

FromtheStandardtoolbar,clicktheSelectElementstoolanddoubleclickontheScaleBar.

ClickontheNumbersandMarkstabintheAlternatingScaleBarPropertiesdialogboxifnecessary.SettheNumbers>Frequencytoends(andzero),andthenclickOK.

ObservetheappearanceoftheUnknownunitsontheScaleBar.Leaveitasit.

SetyourmapscoordinatesystemtoGCS_Luzon_1911.o Hint:

RightclickontheLayersdataframeandselectProperties. SelectthecoordinatesysteminPredefined>GeographicCoordinateSystems>Asia

>Luzon1911.

17. Describewhathappenedtothescalebarandscaletext._______________________________________________________________________________________________________________________________________________________________________

CurrentlyyouareatLayoutView,nowswitchtoDataView.

Measurethedistancesofsomeofthefeatures.

18. Describewhatyouhaveobservedwiththedistances.Doyouthinkthevaluesareaccurate?

________________________________________________________________________________________________________________________________________________________________________

CloseMeasuretoolwindow,andfromtheStandardtoolbar,selectSelectElementstool.

Thecoordinatesystemthatweassumetouseforthemapofphillayerisnotthecorrectone;thereforewehavetochangeitintoamuchsuitablecoordinatesystem.

ThistimewehavetosetthecoordinatesystemofourdataframetoWGS_1984_UTM_Zone_51N,whichisthesuitableprojectionforthePhilippines.Hint:SetthepropertyoftheLayersCoordinateSystemandfromSelectacoordinatesystemexpandUTM,WGS1984,NorthernHemisphereandselectWGS1984UTMZone51N.

Onceagain,measurethedistancesofsomeofthefeatures.

ZoomthemaptoFullExtent .

DoubleclickontheLayersandclickontheGeneraltab(ifnecessary).InsidetheUnitsgroupbox,settheDisplaytoKilometers.

SwitchbacktoLayoutView.

DoubleclickontheScaleBarandclicktheScaleandUnitstab(ifnecessary).InsideUnitsgroupbox,settheDivisionUnitstoKilometersandtheclickOK.

Setthescaleto10,000,000andontheLayouttoolbar,clicktheZoomWholePagebutton .

RelocatetheScaleBarandScaleTexttoitssuitableareaonthemap.

ClicktheFilemenuandclickonExportMap.

OntheExportMapdialogbox,locateyour...\myGISOutputsfolderintheSaveindropdownbox.IntheSaveastypedropdownbox,selectPDFandnameyourfileasmyPhilippinesMap.

LocateyourmyPhilippinesMap.pdffiletoconfirmandopenthefile.

SaveyourmapandcloseArcMap.

Preparedby:Engr.JaniceB.Jamora,MEngandEngr.NoelNavasca,CompENovember2012References:

1. ArcGISdesktopII:ToolsandFunctionalitybyGEODATA,ESRI2. GettingStartedwithGISbySocialScienceandDataSoftware,LelandStandfordJuniorUniversity.3. MappingyourCommunitywithGIS.4. ProjectionandCoordinateSystemsIntroductiontoGISinForestResources(ESRM250),Universityof

Washington.