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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
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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
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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
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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.
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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
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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.
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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.
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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.
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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.
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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
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NGMapMakerInteractive:LandCover—NorthandSouthAmerica
NationalGeographicEvents:GiantTravelingMapofNorthAmerica
Worksheets&Handouts
USGS:TreeSpeciesDistributionMapsforNorthAmerica
Websites
NationalGeographicTravel:NorthAmerica
NationalGeographicEnvironment:ExpeditionBluePlanet—NorthAmerica
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