The AtmosphereThe Atmosphere

The AtmosphereThe Atmosphere

• The atmosphere is the layer of gases that surrounds the planet and makes conditions on Earth suitable for living things.

What is the atmosphere?What is the atmosphere? It holds the oxygen you breathe and protects It holds the oxygen you breathe and protects

you from the sun’s radiation.you from the sun’s radiation. It also helps keep us warm.It also helps keep us warm.

How does it work?How does it work?

Layers of the AtmosphereLayers of the Atmosphere

• Earth’s atmosphere is divided into several different atmospheric layers extending from Earth’s surface outward.

Layers of the AtmosphereLayers of the Atmosphere

• The troposphere is where all the weather occurs.

• It is the closest layer to Earth’s surface.

• It is the layer we live in.

Troposphere: Where We LiveTroposphere: Where We Live

Densest layer – makes up 90% of the Densest layer – makes up 90% of the atmosphere’s massatmosphere’s mass

Contains almost all carbon dioxide, water Contains almost all carbon dioxide, water vapor, weather, and lifevapor, weather, and life

Temps vary greatlyTemps vary greatly

Layers of the AtmosphereLayers of the Atmosphere

• The stratosphere is located directly above the troposphere.

• This is where the ozone layer is.

Stratosphere: Home of the OzoneStratosphere: Home of the Ozone

Temperature rises as altitude rises in this Temperature rises as altitude rises in this layer because ozone absorbs heat from layer because ozone absorbs heat from radiation.radiation.

Ozone protects the troposphere from Ozone protects the troposphere from harmful ultraviolet radiation.harmful ultraviolet radiation.

Layers of the AtmosphereLayers of the Atmosphere

• The next layer up is the mesosphere.

Mesosphere: Middle LayerMesosphere: Middle Layer

Middle and coldest layerMiddle and coldest layer Temp decreases as altitude increasesTemp decreases as altitude increases

IonosphereIonosphere The Ionosphere is in the upper mesosphere, The Ionosphere is in the upper mesosphere,

lower thermosphere. lower thermosphere.

Particles get heated by radiation and Particles get heated by radiation and become electrically charged. become electrically charged.

Charged particles are called ions.Charged particles are called ions.

These particles sometimes radiate energy in These particles sometimes radiate energy in the form of light called auroras.the form of light called auroras.

Thermosphere: The EdgeThermosphere: The Edge

Temp increases with altitudeTemp increases with altitude

Heat is a transfer of thermal Heat is a transfer of thermal energy, but the atoms are so energy, but the atoms are so far apart in the thermosphere far apart in the thermosphere that no heat is transferred. that no heat is transferred.

Although the temperature may Although the temperature may be high, it is not hot.be high, it is not hot.

Layers of the AtmosphereLayers of the Atmosphere

SpaceExosphereThermosphereMesosphereStratosphere (Ozone Layer)Troposphere (Weather, Life)

Earth’s Surface

Names and Their MeaningNames and Their Meaning Sphere = BallSphere = Ball Tropo = turning or changeTropo = turning or change

– Gasses turn and mixGasses turn and mix

Strato = layer Strato = layer – Gasses are layeredGasses are layered

Meso = middleMeso = middle– Middle layerMiddle layer

Thermo = heatThermo = heat– Temperature is highestTemperature is highest

Atmospheric GasesAtmospheric Gases

Nitrogen & Oxygen

• These are the two most common gases found in the atmosphere.

• They can be found throughout all the layers.

CompositionComposition

78% nitrogen (N)78% nitrogen (N) 21% oxygen (O)21% oxygen (O) 1% small particles of 1% small particles of

dust, ash, sea salt, dust, ash, sea salt,

dirt, and smokedirt, and smoke

Atmospheric GasesAtmospheric Gases

Ozone

• Ozone is a form of oxygen

• It is only found in the stratosphere

Atmospheric GasesAtmospheric Gases

Water Vapor & Carbon Dioxide (CO2)

• These are important gases for weather conditions.

• They are found in the troposphere where weather occurs.

Atmospheric TemperaturesAtmospheric Temperatures

Differences in temperature are what separate each layer in the atmosphere from the one above and/or below it.

Atmosphere and TemperatureAtmosphere and Temperature

Air temperature changes with Air temperature changes with altitude. altitude.

Temperature differences Temperature differences mainly result from the way mainly result from the way solar energy is absorbed.solar energy is absorbed.

Some gasses absorb energy Some gasses absorb energy better than others.better than others.

Atmospheric TemperaturesAtmospheric Temperatures

In the troposphere:

• As altitude increases, temperature decreases

Altitude Temperature

Atmospheric TemperaturesAtmospheric Temperatures

In the stratosphere:

• The stratosphere is cold except in its upper region where ozone is located.

Altitude Temperature

Ozone Layer

Atmospheric TemperaturesAtmospheric Temperatures

In the Mesosphere:

• This is the COLDEST layer in the atmosphere.

Altitude Temperature

Atmospheric TemperaturesAtmospheric Temperatures

In the thermosphere:

• Even though the air is thin in the thermosphere, it is very HOT.

Altitude Temperature

Atmospheric TemperaturesAtmospheric Temperatures

Beyond the thermosphere is the exosphere which leads into outer space where it is very cold, because there is little to no atmosphere to absorb the Sun’s heat energy.

Altitude Temperature

Atmospheric TemperaturesAtmospheric Temperatures

Outer Space

Exosphere

Thermosphere

Mesosphere

Stratosphere

Troposphere

Earth’s Surface

Temperature Altitude

Altitude, Temperature, and PressureAltitude, Temperature, and Pressure

Layers of the Layers of the AtmosphereAtmosphere

ThermosphereThermosphere

MesosphereMesosphere

StratosphereStratosphere

TroposphereTroposphere

ReviewReview1.1. Why does temperature vary from one layer Why does temperature vary from one layer

to another?to another?2.2. Why does air pressure decrease as Why does air pressure decrease as

altitude increases?altitude increases?3.3. Why does the thermosphere have high Why does the thermosphere have high

temperatures but does not feel hot?temperatures but does not feel hot?4.4. What two gasses make up most of the What two gasses make up most of the

atmosphere?atmosphere?5.5. What are the layers of the atmosphere, in What are the layers of the atmosphere, in

order from bottom to top?order from bottom to top?