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Module1Antarctica:thelastcontinent1______________________________AntarcticaisthecoldestplaceonEarth.It’salsothedriest.Withannualrainfallclosetozero,Antarcticaistechnicallyadesert.Coveringabout14millionsquarekilometresaroundtheSouthPole,itisthefifthlargestcontinentintheworld.Ahighmountainrange,theTrans-Antarcticrange,runsfromeasttowest,cuttingthecontinentintwo.Therearevolcanoestoo,buttheyarenotveryactive.Antarcticaholds90%oftheworld’sice,andmostofitsfreshwater(70%)isinafrozenstate,ofcourse.98%ofthesurfaceiscoveredpermanentlyintheicecap.Onaverageitistwokilometresthick,butinsomeplacesitreachesadepthoffivekilometres.Strongwindsdrivenbygravityblowfromthepoletothecoastline,whileotherwindsblowroundthecoast.Itisdifficulttoimagineamoreinhospitableplace.2______________________________YetAntarcticaisfullofwildlife,whichhasadaptedtoitsextremeconditions.Therearedifferenttypesofpenguins,flyingbirds,seals,andwhales.ButthelongAntarcticwinternight,whichlastsfor182days(thelongestperiodofcontinuousdarknessonearth),aswellastheextremecoldandlackofrainfall,meansthatfewtypesofplantscansurvivethere.Onlytwotypesoffloweringplantsarefound,whiletherearenotreesonthelargecontinent.Therestoftheplantsaremadeupofmosses,algaeandlichen.Someformsofalgaehaveadaptedtogrowonice.3______________________________Mostoftheicehasbeenthereforthousandsofyears.Asaresult,ithasbecomeawindowonthepast,andcangiveresearcherslotsofusefulinformation.Gasesandminerals,intheformofvolcanicdusttrappedintheice,cantellusalotaboutwhattheworldsclimatewaslikeinpastages.Antarcticrocksarealsoveryimportantforresearch.Mostofthemaremeteoritesfromouterspace.Onerock,knownusthe“Alien”rock,maycontainevidenceofextra-terrestriallife.SincemostAntarcticrocksarcdarkincolour,theystandoutagainstthewhilebackgroundandareeasytoidentifyandcollect.4______________________________Antarcticawasthelastcontinenttobediscovered.ButmorethantwothousandyearsagoGreekgeographersbelievedthattherewasalargelandmassinthesouthwhichbalancedthelandinthenorth.TheycalleditAnti-Arktikos,orAntarctica:theoppositeofArctic.WhenEuropeansdiscoveredthecontinentofAmericainthe15thcentury,thegreatageofexplorationbegan.However,progresstotheSouthPolewasslow.Notuntilthelate18thcenturydidtheBritishexplorerJamesCookcrosstheAntarcticCircle,butheneversawland.Thenin1895,aNorwegiancalledCarstensBorchgrevinkbecamethefirstmantosetfootontheAntarcticmainland.Theracetothepolehadbegun.Itwasfinallyreachedon11thDecember,1911bytheNorwegianRoaldAmundsen.5______________________________TodayscientistsfrommanycountriestraveltoAntarcticatostudyitsresources.Aspiritofinternationalfriendshiphasreplacedtherivalrythatexistedbetweenmanyoftheearlierexplorers.In1961,atreatysignedby12countries,includingBritain,France,andtheUSA,madeAntarcticatheworld'sbiggestnaturereserve.Theaimofthetreatyistopreventthecommercialandmilitaryuseofthecontinent.Inparticular,itaimstokeepAntarcticafreefromnucleartestsandradioactivewaste;topromoteinternationalscientificprojects;andtoendargumentsaboutwhoownstheland.Todaycountriesrepresenting80%oftheworld’spopulationhavesignedthetreaty.Antarcticahasbecomeperhapsthemostsuccessfulsymbolofman’seffortstoworktogetherforprogressandpeace.HowFailureBecameSuccessOn8thAugust,1914,27menwhohadrepliedtoanadvertisementinTheTimesboardedashipleavingfortheAntarctic.ThenameoftheshipwastheEnduranceandthecaptainwasanIrishmancalledErnestShackleton.TheaimofthejourneywastocrossthefrozencontinentviatheSouthPole－ajourneyof1,800miles.Shackletonthoughtthejourneywouldlastsixmonths.Butwhenlandcameintosight,theEndurancebecametrappedintheiceandbegantobreakup.ShackletonandhismenwatchedtheEndurancesinkintotheicysea.Theythenheadednorth,pullingthreelifeboatsbehindthem.Aftersixdays,badweatherforcedthemtogiveupandthemensetupcamponasheetoficewhichbeganslowlymovingacrosstheAntarcticCircle.Theysurvivedontheiceforfivemonths.Then,on16thApril,1915,Shackletonsawland.ItwasElephantIsland－alargerockwithnothinggrowingonit,butmuchbetterthanafloatingpieceofice.Whentheyreachedtheisland,Shackletoncameupwithanidea－itwasariskbuthewouldhavetotakeit.Heandfivemenwouldtakeoneofthelifeboats,andsail800milestoSouthGeorgia,wheretherewasapermanentcamp.Theycouldthenreturntorescuetherestofthemen.IttookShackleton17daystoreachSouthGeorgia.Unfortunatelyhelandedonthewrongsideoftheisland,andhadtowalk36hoursovermountainstoreachthecamp.Thewhalehuntersatthecampcouldn’tbelievetheireyeswhentheysawthesixmenwalkingdownfromthemountains.Shackletonkepthispromise.Morethanthreemonthslater,hereturnedtoElephantIslandtorescuethecrewhehadbeenforcedtoabandon.Hehadfailedtoreachthepole－buthehadsavedthelivesofallhismen.WelcometotheSouthPoles!SouthPoles?Howmanyarethere?Infact,therearethreeSouthPoles:aceremonialPole,whichisonthemovingglacier,ageographicalortruePole,andamagneticPole.whichchangesitspositionaccordingtothemovementoftheEarth.Isitsafe?BecausetheSouthPoleisahighaltitudesite,theglareofthesunlighthereisveryintense.It’salsoreflectedbythesnow,soifyougooutside,remembertowearsunglassesandusesuncream.Ifyoudon’t,there’s