Chapter7
WateronEarth
Lesson1Notes:HowCanOceansbeDescribed?
TheHydrosphere-
• Thehydrospherecoversalittlelessthan3/4oftheEarth’ssurface.
• 3%ofthehydrosphereisinotherplaces.
• ThePacificOceanisthelargest,followedbytheAtlanticOceanandIndianOcean
o OntheMaporGlobe-youcanseealloceansareconnectedinsomeway.
• ThePacificOcean
o Largestocean
o Deepestaswellatabout4,000meters
Salinity-
• Salinity:Ameasureofhowsaltywateris.
• Theoceansgetsaltfromrivers.Riversdissolvesmallamountsofsaltsfromrocksand
soilandcarrythesaltstotheocean.
• Mostofthissaltissodiumchloride—justliketablesalt.
• Placeswhereriverspourfreshwaterintotheoceanhavealowsalinity.Inwarmareas,
oceanwaterevaporatesfairlyquickly.Saltisleftbehind,andtheoceanhasahigher
salinity.
OceanTemperatures-
• Oceanwaterneartheequatorisabout30degreesCelsius(86degreesF)
• Nearthepoles,watercanbeascoldas-2degreesCelsius(28.4degreesF)
OceanResources-
• Onewaytogetsaltisbyevaporatingwater.
• Magnesiumanddrinkingwateralsocomefromoceanwater.Thisisfilteredwhichcan
beexpensive.
Lesson2Notes:WhereisFreshWaterFound?
FreshWater-
• Drinkingwaterisalsocalledfreshwater.
• Freshwaterhascomedissolvedsalts,butmuchlessthanseawater.
• AlmostallFreshWaterstartsoffasrainorsnow;someofitseepsintotheground.
Groundwater-
• Rainorsnowthatsoaksintothegroundiscalledgroundwater.
• Aquifer:Thelayerofrockandsoilthatholdthegroundwater.
• Watertable:Thetoplevelofgroundwaterinanaquiferiscalledthewatertable.
o Thelevelofwaterchangesthroughouttheyear.Itwillrisewhenwaterisadded
byrainorsnow;andwilllowerwhenthereisadrought.
Rivers-
• Surfacewatersinclude:rivers,streamsandlakes.
Lakes-
• Reservoir:isanartificiallakethatformsbehindadam.
Ice-
• MuchoftheEarth’siceisonGreenlandandAntarctica
o Icesheetsinthisareaareseveralmetersthick.
• TheicecapintheNorthPolefloatsontheocean.
• Glaciersandicesheetsaresimilarareasofice.
o Valleyglaciersarefoundinvalleysofhighmountains.Theyflowslowlydownhill.
Astheyflow,theycrushandmoverockwhichchangestheshapeoftheland.
WaterTreatmentPlant-
Part1
Part2
GettingWatertoHomes-
• SmalltownsintheUnitedStatesgettheirwaterfromwatertowersandgroundwater.
• Othertownsmayusesurfacewaterswhichmaycontainbacteriaandneedtobefiltered
forsafety.
• Theprocessoftreatingwatersothatitissafeforusageisinthepictureabove.