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1、Unit1Nothingventured,nothinggainedPartTwo:TeachingResources1.AboutAntarcticaAntarcticaisacontinentsurroundingtheEarth'sSouthPole.ItisthecoldestplaceonEarthandisalmostentirelycoveredbyice;however,itisalsotheworld'slargestdesert.ItisnottobeconfusedwiththeArctic,whichislocatednearth
2、eEarth'sNorthPoleontheoppositesideoftheplanet.AlthoughmythsandspeculationaboutaTerraAustralis("SouthernLand")gobacktoantiquity,thefirstcommonlyacceptedsightingofthecontinentoccurredin1820andthefirstverifiedlandingin1821bytheRussianexpeditionofMikhailLazarevandFabianGottliebvonBel
3、lingshausen.(SeealsoHistoryofAntarctica.)Withanareaof13,200,000km²,Antarcticaisthefifthlargestcontinent,afterAsia,Africa,NorthAmerica,andSouthAmerica.However,itisbyfarthesmallestinpopulation:indeed,ithasnopermanentpopulationatall.Itisalsothecontinentwiththehighestaveragealtitude,
4、andthelowestaveragehumidityofanycontinentonEarth,aswellasthelowestaveragetemperature.2.ClimateofAntarctica.Antarcticaisthecoldestplaceonearth.Temperaturesreachaminimumofbetween-85and-90degreesCelsiusinthewinterandabout30degreeshigherinthesummermonths.Weatherfrontsrarelypenetratef
5、arintothecontinent,leavingthecentercoldanddry.Thereislittleprecipitationoverthecontinent,buticetherecanlastforextendedtimeperiods.NearlyallofAntarcticaiscoveredbyanicesheetthatis,onaverage,2.5kilometersthick.Attheedgeofthecontinent,strongkatabaticwindsoffthepolarplateauoftenblowa
6、tstormforce.Intheinterior,however,windspeedsareoftenmoderate.Dependingonthelatitude,longperiodsofconstantdarkness,orconstantsunlight,meanthatclimatesfamiliartohumansarenotgenerallyavailableonthecontinent.Geography3.GeographyofAntarcticaThecontinentofAntarcticaislocatedmostlysouth
7、oftheAntarcticCircle,surroundedbytheSouthernOcean.PhysicallyAntarcticaisdividedintwobymountainsclosetotheneckbetweentheRossSeaandtheWeddellSea.TheportionofthecontinentwestoftheWeddellSeaandeastoftheRossSeaiscalledWesternAntarcticaandtheremainderEasternAntarctica,sincetheycorrespo
8、ndroughlytotheeasternandwesternhemispher
