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Yourwebbrowser(Safari7)isoutofdate.Formoresecurity,comfortand thebestexperienceonthissite: Updateyourbrowser Ignore N O RT H A M E R I C A: P H Y S I C A L G E O G RA P H Y Forthecompleteencyclopedicentrywithmediaresources,visit: http://www.nationalgeographic.org/encyclopedia/north-america-physicalgeography/ NorthAmerica,thethird-largestcontinent,extendsfromthetinyAleutian IslandsinthenorthwesttotheIsthmusofPanamainthesouth.Thecontinent includestheenormousislandofGreenlandinthenortheastandthesmallisland countriesandterritoriesthatdottheCaribbeanSeaandwesternNorthAtlantic Ocean.Inthefarnorth,thecontinentstretcheshalfwayaroundtheworld,from GreenlandtotheAleutians.ButatPanama’snarrowestpart,thecontinentisjust 50kilometers(31miles)across. NorthAmerica’sphysicalgeography,environmentandresources,andhuman geographycanbeconsideredseparately. NorthAmericacanbedividedintofivephysicalregions:themountainouswest, theGreatPlains,theCanadianShield,thevariedeasternregion,andthe Caribbean.MexicoandCentralAmerica’swesterncoastareconnectedtothe mountainouswest,whileitslowlandsandcoastalplainsextendintotheeastern region. Withintheseregionsareallthemajortypesofbiomesintheworld.Abiomeisa communityofanimalsandplantsspreadingoveranextensiveareawitha relativelyuniformclimate.SomediversebiomesrepresentedinNorthAmerica includedesert,grassland,tundra,andcoralreefs. WesternRegion 1of10 Youngmountainsriseinthewest.Themostfamiliarofthesemountainsare probablytheRockies,NorthAmerica’slargestchain.TheRockiesstretchfrom theprovinceofBritishColumbia,Canada,totheU.S.stateofNewMexico. TheRockyMountainsarepartofasystemofparallelmountainrangesknownas theCordilleras.Acordilleraisalongseriesofmountainranges.Although cordillerasexistallovertheworld,inNorthAmerica,“theCordilleras”indicate themassivemountainrangesinthewesternpartofthecontinent.The CordillerasextendfromCanadaallthewaytotheIsthmusofPanama. TheSierraMadremountainsystemispartoftheCordilleras.TheSierraMadre stretchfromthesouthwesternUnitedStatestoHonduras.TheSierraMadre includemanyhighvolcanoes(upto5,636meters,or18,500feet)thatstretch acrossMexicosouthofthecitiesofGuadalajaraandMexicoCity. VolcanicmountainrangesinGuatemala,Honduras,Nicaragua,CostaRica,and PanamaarealsoconsideredpartoftheCordilleras.Volcaniceruptionsand earthquakesoccurfrequentlyinthisregion.Volcanicactivitycandestroytowns andcities.Italsocontributestotherich,fertilesoilsoftheregion. SomeoftheEarth’syoungestmountainsareintheCascadeRangeoftheU.S. statesofWashington,Oregon,andCalifornia.Somepeaksbegantoformonly aboutamillionyearsago—ablinkofaneyeinEarth’slonghistory.The mountainsincludetemperaterainforest—abiomeuniquetothearea.The temperaterainforestreceivesanincredibleamountofprecipitation,between 254to508centimeters(100to200inches)annually.However,itscoolwinters andmildsummerspromotethegrowthofmosses,ferns,fungi,andlichens. Thetemperaterainforestsupportsawidevarietyoflife.TheSitkaspruce, westernredcedar,andDouglasfiraretreesnativetoNorthAmerica’s temperaterainforest.Someofthesetreesgrowtomorethan90meters(300 feet)talland3meters(10feet)indiameter.Blackbears,Rooseveltelk,and 2of10 marmotsareindigenousanimalspecies. ThethreemajordesertregionsofNorthAmerica—theSonoran,Mojave,and Chihuahuan—areallintheAmericansouthwestandnorthernMexico.These largedesertsarelocatedintherainshadowsofnearbymountains.The mountainsblockprecipitationandacceleratethemovementofhot,drywind overtheseregions.TheSonoranisintherainshadowoftheCoastRanges,the MojaveisintheshadowoftheSierraNevada,andtheChihuahuanisinthe shadowoftheSierraMadre. Notabledesertplantspeciesincludesthesaguarocactus,Joshuatree,and mesquite.Animalspeciesincludetheroadrunner,Gilamonster,andrattlesnake. Inadditiontomountains,deserts,andforests,thenorthernpartofthewestern regionofNorthAmericaalsohastherichestdepositsofoilandnaturalgason thecontinent.Mostofthesedepositsarelocatedoffshore,intheArcticand PacificOceans. GreatPlains TheGreatPlainslieinthemiddleofthecontinent.Deep,richsoilblanketslarge areasoftheplainsinCanadaandtheUnitedStates.Graingrowninthisregion, calledthe“BreadbasketofNorthAmerica,”feedsalargepartoftheworld.The GreatPlainsarealsohometorichdepositsofoilandnaturalgas. Muchofthefertilesoilwasformedfrommaterialdepositedduringthemost recentglacialperiod.Thisiceagereacheditspeakabout18,000yearsago.As glaciersretreated,streamsofmeltedicedroppedsedimentontheland, buildinglayersofproductivesoil. ThegrasslandorprairieregionsoftheGreatPlainsmakeupthelargestbiome inNorthAmerica.Extremeweatherpreventsthegrowthoflargeplantsbutis perfectlysuitedtothenativegrassesthatdominatetheregion. 3of10 Nativegrassesvaryinsizefrom2meters(7feet)intallgrassprairiestoonly20 or25centimeters(8or10inches)inshortgrassprairies.Nativeanimalspecies includebison,prairiedogs,andgrasshoppers. CanadianShield TheCanadianShieldisaraisedbutrelativelyflatplateau.Itextendsover eastern,central,andnorthwesternCanada.TheCanadianShieldis characterizedbyarockylandscapepockedbyanastoundingnumberoflakes. Thetundra,stretchingalongthenorthernbordersofAlaskaandCanadatothe HudsonBayarea,isabiomecommontotheCanadianShield.Tundraiswhere lowtemperaturesandprecipitationlevelshindertreegrowth.Thetundrais characterizedbypermafrost—soilthatisfrozenfortwoormoreyears.This permafrostkeepsmoisturenearthesoil’ssurface,promotingvegetationgrowth evenintheextreme,Arcticconditionsofthetundra. Duringthesummer,thistoplayerofsoilthawslessthan10centimeters(onlya fewinches)down,formingnumerousshallowlakes,ponds,andbogs.Lichens, mosses,algae,andsucculentstakeadvantageoftheseshallowwaters.Inturn, theyprovidefoodforthecaribouandmuskoxthataretypicalofthisarea. EasternRegion ThisvariedregionincludestheAppalachianMountainsandtheAtlanticcoastal plain. NorthAmerica’soldermountainranges,includingtheAppalachians,risenear theeastcoastoftheUnitedStatesandCanada.Theseareashavebeenmined forrichdepositsofcoalandothermineralsforhundredsofyears. TheAtlanticcoastalplainextendsfromriver,marsh,andwetlandregionseast 4of10 ofthemountainstowardthesandybeachesoftheAtlanticcoast.Wetlandareas areabiomeoftheeasternregionandconsistofareasoflandwhosesoilis saturatedwithpermanentorseasonalmoisture.TheFloridaEvergladesisthe largestwetlandsystemintheUnitedStates,coveringmorethan11,137square kilometers(4,300squaremiles)ofsouthernFlorida. TheEvergladesisabiologicallydiverseregionandcontainsseveralbordering ecosystems.Sawgrassmarshesarethemosticonicplantcommunityofthe Evergladesandthriveontheslow-movingwaterofthewetlands.Alligatorsnest inthesawgrass,whilewadingbirdssuchasegrets,herons,spoonbills,andibises maketheirbreedinggroundsinotherwetlandtreespecies,suchascypressand mangrove. CaribbeanRegion TheCaribbeanRegionincludesmorethan7,000islands,islets,reefs,andcays. Theregion’sislandsandsmallerisletsarevariedintheirtopography;somehave relativelyflatandsandyterrainwhileothersarerugged,mountainous,and volcanic. ThecoralreefsandcaysoftheCaribbeanSeaareamongthemostspectacular biomesinNorthAmerica.Areefisaridgeofjaggedrock,coral,orsandjust aboveorbelowthesurfaceofthesea.Somecoralreefssurroundislands,such astheBahamas,Antigua,andBarbados.OthersarefoundofftheFloridaKeys, achainofcays—smallislandssituatedonacoralreefplatform—nearthe southerncoastoftheU.S.stateofFlorida. Coralreefsaremadeofmillionsoftinyanimals—corals—thatformahardshell aroundtheirbodies.Thishardsurfaceprovidesarichcommunityforalgaeand plantssuchasseagrass.Brightlycoloredtropicalfish,aswellassharks,sea turtles,seastars,andseahorses,areanimalsnativetotheCaribbean’scoral reefs. 5of10 NaturalWonders NorthAmerica’svariedlandscapefeaturesmanynaturalwonders.Ithasdeep canyons,suchasCopperCanyonintheMexicanstateofChihuahua.Denali,the continent’shighestpeak,standsat6,194meters(20,320feet)withinDenali NationalParkandPreserveintheU.S.stateofAlaska.YellowstoneNational Park,intheU.S.statesofWyoming,Montana,andIdaho,hassomeofthe world’smostactivegeysers.Canada’sBayofFundyhasthegreatesttidalrange intheworld.TheGreatLakesformtheplanet’slargestareaoffreshwater.The MississippiRiver,at3,730kilometers(2,320miles)long,isoneofthelongest riversystemsintheworldanddrainsallorpartsof31U.S.states. Vocabulary Term Partof accelerate verb Arctic noun beach noun biome noun bog noun border noun Canadian shield cay Definition Speech noun noun toincreasespeedorvelocity. regionatEarth'sextremenorth,encompassedbythe ArcticCircle. narrowstripoflandthatliesalongabodyofwater. areaoftheplanetwhichcanbeclassifiedaccordingtothe plantandanimallifeinit. wetlandofsoftgroundmademostlyofdecayingplant matter. naturalorartificiallineseparatingtwopiecesofland. rockyplateauextendingthroughmostofnorthernand centralCanada. small,lowislandonacoralreef.Alsocalledakey. allweatherconditionsforagivenlocationoveraperiodof climate noun time. coal noun dark,solidfossilfuelminedfromtheearth. coastalplainnoun low,flatlandlyingnexttotheocean. 6of10 Term Partof Definition Speech continent noun coralreef noun cordillera noun desert noun diverse adjectivevariedorhavingmanydifferenttypes. earthquake noun ecosystem noun environment noun Everglades noun oneofthesevenmainlandmassesonEarth. rockyoceanfeaturesmadeupofmillionsofcoral skeletons. chainofmountainranges. areaoflandthatreceivesnomorethan25centimeters (10inches)ofprecipitationayear. thesuddenshakingofEarth'scrustcausedbytherelease ofenergyalongfaultlinesorfromvolcanicactivity. communityandinteractionsoflivingandnonlivingthings inanarea. conditionsthatsurroundandinfluenceanorganismor community. vastswampyregionflowingsouthofLakeOkeechobeein Florida. fertile adjectiveabletoproducecropsorsustainagriculture. forest noun freshwater noun geyser glacial period grassland noun noun noun GreatPlains noun hinder human geography iconic verb noun ecosystemfilledwithtreesandunderbrush. waterthatisnotsalty. naturalhotspringthatsometimeseruptswithwateror steam. timeoflong-termloweringoftemperaturesonEarth.Also knownasaniceage. ecosystemwithlarge,flatareasofgrasses. grasslandregionofNorthAmerica,betweentheRocky MountainsandtheMississippiRiver. todelayorholdback. thestudyofthewayhumancommunitiesandsystems interactwiththeirenvironment. eventorsymbolrepresentingabelief,nation,or adjective community. 7of10 Term Partof Definition Speech indigenous adjectivecharacteristictoorofaspecificplace. island noun bodyoflandsurroundedbywater. isthmus noun narrowstripoflandconnectingtwolargerlandmasses. lake noun bodyofwatersurroundedbyland. lichen noun marsh noun mineral noun mountain range noun naturalgas noun organismcomposedofafungusorfungiandanalgaor cyanobacterium. wetlandareausuallycoveredbyashallowlayerof seawaterorfreshwater. inorganicmaterialthathasacharacteristicchemical compositionandspecificcrystalstructure. seriesorchainofmountainsthatareclosetogether. typeoffossilfuelmadeupmostlyofthegasmethane. offshore havingtodowithfacilitiesorresourceslocated adjective underwater,usuallymilesfromthecoast. oil noun permafrost noun physical geography noun plateau noun prairie noun precipitationnoun province rainforest noun noun fossilfuelformedfromtheremainsofmarineplantsand animals.Alsoknownaspetroleumorcrudeoil. permanentlyfrozenlayeroftheEarth'ssurface. studyofthenaturalfeaturesandprocessesoftheEarth. largeregionthatishigherthanthesurroundingareaand relativelyflat. largegrassland;usuallyassociatedwiththeMississippi RiverValleyintheUnitedStates. allformsinwhichwaterfallstoEarthfromthe atmosphere. divisionofacountrylargerthanatownorcounty. areaoftall,mostlyevergreentreesandahighamountof rainfall. 8of10 Term Partof Definition Speech rainshadow noun drylandonthesideofamountainfacingawayfrom prevailingwinds. anyareaonEarthwithoneormorecommon region noun resource noun river noun saturate verb sediment noun soil noun succulent noun temperate adjectivemoderate. tidalrange noun characteristics.Regionsarethebasicunitsofgeography. availablesupplyofmaterials,goods,orservices. Resourcescanbenaturalorhuman. largestreamofflowingfreshwater. tofillonesubstancewithasmuchofanothersubstanceas itcantake. solidmaterialtransportedanddepositedbywater,ice,and wind. toplayeroftheEarth'ssurfacewhereplantscangrow. typeofplantthathasthickleavesandstemsforstoring water. thedifferenceinheightbetweenanarea'shightideand lowtide. topography noun studyoftheshapeofthesurfacefeaturesofanarea. tundra cold,treelessregioninArcticandAntarcticclimates. volcanic eruption noun noun activitythatincludesadischargeofgas,ash,orlavafrom avolcano. stateoftheatmosphere,includingtemperature, weather noun atmosphericpressure,wind,humidity,precipitation,and cloudiness. wetland noun areaoflandcoveredbyshallowwaterorsaturatedby water. movementofair(fromahighpressurezonetoalow wind noun pressurezone)causedbytheunevenheatingoftheEarth bythesun. Maps 9of10 NGMapMakerInteractive:LandCover—NorthandSouthAmerica NationalGeographicEvents:GiantTravelingMapofNorthAmerica Worksheets&Handouts USGS:TreeSpeciesDistributionMapsforNorthAmerica Websites NationalGeographicTravel:NorthAmerica NationalGeographicEnvironment:ExpeditionBluePlanet—NorthAmerica ©1996–2017NationalGeographicSociety.Allrightsreserved. 10of10