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Section1
A. Atmosl!here-thin layerof air that protectsthe Earth'ssurfacefrom
extremetemperaturesand harmful Sun rays
B. Atmosphericmakeup-mixture of gases,~,
and liquids
1. Early atmospherewasmuch different than today.
b. More than 2 billion yearsagosim~le organis~s beganproducing oxygen.
c. Eventuallyoxygenformed an ozonelayer that protectedEarth from harmful rays.
d. ~
plantsand diverselife forms developed.
2. Atmospheric ~
and argon.
include nitrogen (78%), oxygen (21 %), carbon dioxide, water vapor,
a. Atmosphere is changing with the introduction of pollutants:
use is increasing the amount of carbon dioxide.
increasing human energy
b. Pollutantsmi:xwith oxygenand other chemicalsto form ~.
3. ~
include dust)salt)and pollen.
4. Liquids includewater dropletsand dropletsfrom volcanoes.
C. M mainlayersof theatmosphere
1. ~
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a. Lowestlayer,wherehumanslive, is the tro~os~her~,which extendsabout 10kIn up, and
containsmost of the watervapor and gases.
b. Extending from 10 km to 50 km above Earth, the stratosphere contains higher levels of
ozone.
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a. Mesosl2here extends from
50 km to 85 km and is the layer in which
shooting
stars are
visible.
b. Thickest
part of atmosphere
is from
85 km to 500 km and is called the thermos12here
for
its high temperatures.
c. Within the thermosphere is a layer of charged particles called the ionos12here that can
help carry radio waves.
d Exos12here--outerlayer of atmospherein which the spaceshuttle flies has very few molecules
D. Atmost?:heric
t?:ressu~-moleculescloserto the surfaceare more denselypacked(at higher
pressure)togetherthan thosehigher in the atmospherebecauseof the massof gasespressing
down on them from higher in the atmosphere.
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Atmosphere
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E. Teml2eraturein atmospheric layers
1.
The troposphereis warmedprimarily by the Earth'ssurface;temperaturedecreases
as
altitude increasesin this layer.
2. Temperaturesincreaseasaltitude increasesin the stratosphere,particularly the upper
portion becauseozoneabsorbsenergyfrom the Sun.
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3. Temperaturesdecreasewith altitude in the mesosphere.
4. Thermosphereand exospherearethe first to receivethe Sun'srays,so they arevery ~.
F.
Ozonelayer-about 19krn to 48 krn aboveEarth in the stratosphere,this layerof 3-atom
molecules protects the Earth from the Sun's harmful ultraviolet radiation
1. Life on Earth,aswe know it, de12ends
on it.
2. Pollutants called chlorofluorocarbons
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(CFCs) are destroying the ozone layer.
a. CFCsareusedin refrigerators,air conditioners,aerosolsprays,and foam packaging.
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b. If theseproductsdevelopa leak,CFCscan enter the atmos12here.
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3. The ozonelayerhasa largehole over Antarcticaand a smallerone overthe north pole.
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DISCUSSION
QUESTION:
What is the ionosphere?A layer of chargedparticles located in the thermosphere
Section2
A. Someenergyfrom the Sun is reflectedbackinto ~,
someis absorbedby the atmos12here,
andsomeis absorbed
by 19.rulandwateron Earth'ssurface.
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B. ~--energy
that flowsfrom an objectwith a highertemperatureto onewith a lowertemperature
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1. Radiation-energy transferredin raysor waves
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2. Conduction-transfer
of energywhen moleculesbump into eachother through contact
3. Convection-transfer of heat by the flow of a material
.
a. Moleculesmove closertogether,making the air more dense,and air pressurerises.
b. Cold air ~,
c. The~
pushing up warm air, which then cools and sinks, pushing up more warm air.
cycle. -watermovesback and forth betweenEarth'satmosphereand surface
1. Energyfrom the Sun causeswater to eva12orate
from the hydrosphere,and rise asvapor.
2. Watervapor in the atmospherecan cool and return to liquid form through condensation.
a. When water vapor condenses,cloudsof tiny water dropletsmay form.
b. Waterdropletscollide to form largerprecipitation.
AtmosphereT3
3. Waterdrops fall backto Earth asI2recil2itation.
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D. Earth'satmosphereis unique-it holdsjust the right amount of the Sun'sener~ to supportlife
DISCUSSIONQUESTION:
What arethreewaysthat heat energyis transferredthrough the atmosphere?Radiation,
conduction, convection
Section3
Air Movement
A. :wi!ld-forms when air in an areaof high pressu~e
movesto an areaof lower pressure
1. Different areasof Earth receivedifferent amountsof the Sun'sradiation.
a. The equator'swarm air, being lessdense,is pushedupward by denser,~
b. The pole'scold air, being more ~,
2. The Coriolis effect-rotation
air.
sinksand movesalong Earth'ssurface.
of the Earth causesmoving air and water to changedirection
to the right north of theequatorandleft southof theequator
B. Globalwinds-wind patterns,causedby convectioncurrentscombinedwith the Coriolis
effect,of Earth that affectthe world's weather
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1~ Nearthe equator,very little wind and daily rain patternscalledthe doldrums
2. Surfacewinds
a. Betweenthe equatorand 30' latitude (north and south) are steadytrade winds
b. Between 30. and 60. latitude (north and south) the ~revailing westerlies blow in the
opposite direction from the trade winds
c. Polareasterliesblow from northeastto southwestnearthe north pole and from southeast
to northwestnearthe south pole
3. Upper troposphere-narrow belts of strong winds calledjet streams
a. Jetstreammoves~
in the winter.
b. Helps storms develop and move acrossthe country
C. Local wind systems-affect lQ.9!l weather
1. Sea breezes-a convection current blows wind from the cooler sea toward warmer land
during the day
2. Land breezes--at night, air movestoward the water asthe land cools more rapidly than the water
DISCUSSIONQUESTION:
What is the Coriolis effect? Rotation of the Earth makesair and water appear to turn right north of
the equator and left south of the equator
T4 Atmosphere