AtmosphereAtmosphere

AtmosphereAtmosphereComposition:Composition:

Gases - nitrogen, oxygen, argon, other gasesGases - nitrogen, oxygen, argon, other gasesCompounds – carbon dioxide, water vaporCompounds – carbon dioxide, water vapor

Atmospheric pressure – Atmospheric pressure – Gravity pulling the gases Gravity pulling the gases of the atmosphere towards the earth’s surface.of the atmosphere towards the earth’s surface.

BarometerBarometer – Instrument that measures – Instrument that measures atmospheric pressure.atmospheric pressure.

Ex. – mercury barometerEx. – mercury barometerStandard atmospheric pressureStandard atmospheric pressure – average – average atmospheric pressure at sea level. (29.92) atmospheric pressure at sea level. (29.92)

Mercury BarometerMercury Barometer

Layers of the AtmosphereLayers of the Atmosphere(Troposphere)(Troposphere)

TroposphereTroposphere – layer closest to the earth’s surface. – layer closest to the earth’s surface.- Almost all the water vapor and carbon dioxide is - Almost all the water vapor and carbon dioxide is found in this layer.found in this layer.- Temperature decreases at 6.5- Temperature decreases at 6.5°C/km until you °C/km until you reach 10km, where is stops decreasing.reach 10km, where is stops decreasing.- - TropopauseTropopause – the upper boundary of the – the upper boundary of the troposphere, where the temp decrease stops. troposphere, where the temp decrease stops.

StratosphereStratosphereStratosphere – Stratosphere – Extends upward to an altitude of Extends upward to an altitude of

50km.50km.

-- Contains almost all the Ozone (OContains almost all the Ozone (O33))

- - Stratopause –Stratopause – Marks the upper end of the Marks the upper end of the stratospherestratosphere

MesosphereMesosphere

Mesosphere – Mesosphere – extends to an altitude of 80 km.extends to an altitude of 80 km.- the coldest layer of the atmosphere (-90- the coldest layer of the atmosphere (-90°C)°C)- - MesopauseMesopause – upper boundary of the – upper boundary of the mesosphere.mesosphere.

ThermosphereThermosphere

Thermosphere – Thermosphere – the upper layer of our the upper layer of our atmosphere.atmosphere.- the air is very thin, cannot be measured with a - the air is very thin, cannot be measured with a regular thermometer.regular thermometer.- - IonosphereIonosphere - the lower region of the - the lower region of the thermosphere.thermosphere.- - ExosphereExosphere – above the thermosphere where the – above the thermosphere where the earth’s atmosphere blends in with space.earth’s atmosphere blends in with space.