Australia.docx

Australia.docx

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Australia

Australia:

GeographyofAustralia

Continent

Australia

Region

Oceania

Coordinates

27°S144°E/27°S144°E/-27;144Coordinates:

27°S144°E/27°S144°E/-27;144

Area

Ranked6th

7,686,850 km2

2,967,910 sq mi

99%land

1%water

Coastline

25,765 km（16,000 mi）

Borders

0 km

Highestpoint

MountKosciuszko

2,234m（7,310 ft）

Lowestpoint

LakeEyre

-15m（-49ft）

Longestriver

MurrayRiver2,375 km（1,476 mi）

Largestlake

LakeEyre9,500 km²（3,668 sq mi）

Australiaisacountry,anisland,andacontinent.ItislocatedinOceaniabetweentheIndianOceanandtheSouthPacificOceanat

27°S144°E/27°S144°E/-27;144.Itisthesixthlargestcountryintheworldwithatotalareaof7,686,850squarekilometers（2,967,909 sq. mi）（includingLordHoweIslandandMacquarieIsland）,makingitslightlysmallerthanthecontiguous48statesoftheUnitedStatesand31.5timeslargerthantheUnitedKingdom.

TheAustralianmainlandhasatotalcoastlinelengthof35,876 km（22,292mi）withanadditional23,859 km（14,825 mi）ofislandcoastlines.[1]Thereare758estuariesaroundthecountrywithmostlocatedinthetropicalandsub-tropicalzones.[2]AustraliaclaimsanextensiveExclusiveEconomicZoneof8,148,250squarekilometres（3,146,057 sq. mi）.ThisexclusiveeconomiczonedoesnotincludetheAustralianAntarcticTerritory.Australiahasthelargestareaofoceanjurisdictionofanycountryonearth.[3]Ithasnolandborders.ThenorthernmostpointsofthecountryaretheCapeYorkPeninsulaofQueenslandandtheTopEndoftheNorthernTerritory.

ThewesternhalfofAustraliaconsistsoftheWesternPlateau,whichrisestomountainheightsnearthewestcoastandfallstolowerelevationsnearthecontinentalcenter.TheWesternPlateauregionisgenerallyflat,thoughbrokenbyvariousmountainrangessuchastheHamersleyRange,theMacDonnellRanges,andtheMusgraveRange.SurfacewaterisgenerallylackingintheWesternPlateau,althoughthereareseverallargerriversinthewestandnorth,suchastheMurchison,Ashburton,andVictoriariver.

TheEasternHighlands,orGreatDividingRange,lieneartheeasterncoastofAustralia,separatingtherelativelynarroweasterncoastalplainfromtherestofthecontinent.TheseEasternAustraliantemperateforestshavethegreatestrelief,themostrainfall,themostabundantandvariedfloraandfauna,andthedensesthumansettlement.

BetweentheEasternHighlandsandtheWesternPlateau,lietheCentralLowlands,whicharemadeupoftheGreatArtesianBasinandAustralia'slargestriversystems,Murray-DarlingBasinandLakeEyreBasin.

OfftheeasterncoastofAustraliaistheworld'slargestcoralreefcomplex,theGreatBarrierReef.TheStateofTasmania,alargeandmountainousisland,residesinthesouth-easterncornerofAustralia.

[edit]Geology

Mainarticle:

GeologyofAustralia

BasicgeologicalunitsofAustralia

Australiaisthelowest,flattest,andoldestcontinentallandmassonEarth[citationneeded]andithashadarelativelystablegeologicalhistory.GeologicalforcessuchastectonicupliftofmountainrangesorclashesbetweentectonicplatesoccurredmainlyinAustralia'searlyhistory,whenitwasstillapartofGondwana.ItshighestpeakisMountKosciuszkoat2,228metres（7,310 ft）,whichisrelativelylowincomparisontothehighestmountainsonothercontinents.ErosionhasheavilyweatheredAustralia'ssurface.

Australiaissituatedinthemiddleofthetectonicplate,andthereforecurrentlyhasnoactivevolcanism.Minorearthquakeswhichproducenodamageoccurregularly,whilemajorearthquakesmeasuringgreaterthanmagnitude6occuronaverageeveryfiveyears.[4]Theterrainismostlylowplateauwithdeserts,rangelandsandafertileplaininthesoutheast.TasmaniaandtheAustralianAlpsdonotcontainanypermanenticefieldsorglaciers,althoughtheymayhaveexistedinthepast.TheGreatBarrierReef,byfartheworld'slargestcoralreef,liesashortdistanceoffthenorth-eastcoast.MountAugustus,inWesternAustralia,isthelargestmonolithintheworld.

[edit]Regions

Mainarticle:

RegionsofAustralia

TheAustraliancontinentallandmassconsistsof6distinctlandformdivisions.[5]Theseare:

∙TheEasternHighlands—includingtheGreatDividingRange,thefertileBrigalowBeltstripofgrasslandbehindtheeastcoast,andtheEasternUplands

∙TheEasternalluvialPlainsandLowlands—MurrayDarlingbasincoverssouthernpart,alsoincludespartsoftheLakeEyreBasinandextendstotheGulfofCarpentaria

∙TheSouthAustralianHighlands—includingtheFlindersRange,EyrePeninsulaandYorkePeninsula

∙TheWesternPlateau—includingtheNullarborPlain

∙TheCentralDeserts

∙NorthernPlateauandBasins—includingtheTopEnd

Seealso:

EcoregionsinAustralia

[edit]Hydrology

Reliefmapshowingmajorriversandlakes

BecausemuchofAustralia'sinteriorisarid,thelowaverageannualrainfallmeansinteriorriversareoftendryandlakesempty.Theheadwatersofsomewaterwaysarelocatedintropicalregionswheresummerrainscreateahighrateofdischarge.FloodeventsdrasticallyalterthedryenvironmentinwhichtheecologyofcentralAustraliahashadtoadapttotheboomandbustcycle.

TheGreatArtesianBasinisanimportantsourceofwater,theworld'slargestanddeepestfreshwaterbasin.Accesstowaterfromthebasinhasledtotheexpansionofgrazingintoareasthatwerepreviouslyfartoodryforlivestock.Townsandcitiesacrossthecountrysometimesfacemajorwaterstorageandusagecrisisinwhichrestrictionsandothermeasuresareimplementedtoreducewaterconsumption.Waterrestrictionsarebasedonagradientofactivitiesthatbecomeprogressivelybannedasthesituationworsens.

BillabongsistheAustraliannamegiventooxbowlakesthatcanformalongameanderingriver'scourse.Inaworld-widecomparisonofheight,Australia'swaterfallsarerelativelyinsignificant,withthelongestdropranked135thaccordingtotheWorldWaterfallDatabase.[6]

Seealso:

WatersecurityinAustralia

[edit]Politicalgeography

Mainarticle:

StatesandterritoriesofAustralia

AclickablemapofAustralia'sstatesandmainlandterritories

Australiaconsistsofsixstates,twomajormainlandterritories,andotherminorterritories.ThestatesareNewSouthWales,Queensland,SouthAustralia,Tasmania,VictoriaandWesternAustralia.ThetwomajormainlandterritoriesaretheNorthernTerritoryandtheAustralianCapitalTerritory.

Australiaalsohasseveralminorterritories;thefederalgovernmentadministersaseparateareawithinNewSouthWales,theJervisBayTerritory,asanavalbaseandseaportforthenationalcapital.InadditionAustraliahasthefollowing,inhabited,externalterritories:

NorfolkIsland,ChristmasIsland,Cocos（Keeling）Islands,andseverallargelyuninhabitedexternalterritories:

AshmoreandCartierIslands,CoralSeaIslands,HeardIslandandMcDonaldIslandsandtheAustralianAntarcticTerritory.

Seealso:

SubdivisionsofAustralia andSuburbsandlocalities（Australia）

[edit]Climate

Mainarticle:

ClimateofAustralia

ClimatemapofAustralia

ByfarthelargestpartofAustraliaisaridorsemi-arid–about70%ofthelandmass.Atotalof18%ofAustralia'smainlandisdesert.[7][deadlink]Onlythesouth-eastandsouth-westcornershaveatemperateclimateandmoderatelyfertilesoil.Thenorthernpartofthecountryhasatropicalclimate:

partistropicalrainforests,partgrasslands,andpartdesert.

Rainfallishighlyvariable,withfrequentdroughtslastingseveralseasonsthoughttobecausedinpartbytheElNiño-SouthernOscillation.Occasionallyaduststormwillblanketaregionorevenseveralstatesandtherearereportsoftheoccasionallargetornado.Risinglevelsofsalinityanddesertificationinsomeareasisravagingthelandscape.

Australia'stropical/subtropicallocationandcoldwatersoffthewesterncoastmakemostofwesternAustraliaahotdesertwitharidity,amarkedfeatureofthegreaterpartofthecontinent.Thesecoldwatersproducelittlemoistureneededonthemainland.A2005studybyAustralianandAmericanresearchersinvestigatedthedesertificationoftheinterior,andsuggestedthatoneexplanationwasrelatedtohumansettlerswhoarrivedabout50,000yearsago.RegularburningbythesesettlerscouldhavepreventedmonsoonsfromreachinginteriorAustralia.Theoutbackcovers70percentofthecontinent.

[edit]Naturalhazards

Cyclonesalongthenortherncoasts;severethunderstorms,droughtsandoccasionalfloods;frequentbushfires.

[edit]Environment

Mainarticle:

EnvironmentalissuesinAustralia

Currentissues:

soilerosionfromovergrazing,industrialdevelopment,urbanization,andpoorfarmingpractices;soilsalinityrisingduetotheuseofpoorqualitywater;desertification（partlyasaresultoftheintroductionbyEuropeansettlersofRabbits）;introducedpestspecies;clearingforagriculturalpurposesthreatensthenaturalhabitatofmanyuniqueanimalandplantspecies;theGreatBarrierReefoffthenortheastcoast,thelargestcoralreefintheworld,isthreatenedbyincreasedshippinganditspopularityasatouristsite;limitednaturalfreshwaterresources;threatsfrominvasivespecies.

Statesandterritories

Mainarticle:

StatesandterritoriesofAustralia

AclickablemapofAustralia'sstatesandmainlandterritories

Australiahassixstates—NewSouthWales,Queensland,SouthAustralia,Tasmania,Victoria,andWesternAustralia—andtwomajormainlandterritories—theNorthernTerritoryandtheAustralianCapitalTerritory（ACT）.Inmostrespectsthesetwoterritoriesfunctionasstates,buttheCommonwealthParliamentcanoverrideanylegisl