AtmosphereAtmosphere

• thin layer of air that protects the thin layer of air that protects the Earth’s surface from extreme Earth’s surface from extreme temperatures and harmful Sun rays.temperatures and harmful Sun rays.

Atmospheric makeupAtmospheric makeup• mixture of gases, solids, and liquids.mixture of gases, solids, and liquids.

Early atmosphere was much Early atmosphere was much different than todaydifferent than today

• volcanoes produced nitrogen and volcanoes produced nitrogen and carbon dioxide, but little oxygen.carbon dioxide, but little oxygen.

• More than 2 billion years ago simple More than 2 billion years ago simple organisms began producing oxygen.organisms began producing oxygen.

• Eventually oxygen formed an ozone Eventually oxygen formed an ozone layer that protected Earth from layer that protected Earth from harmful rays.harmful rays.

• Green plants and diverse life forms Green plants and diverse life forms developed.developed.

Atmospheric gases include Atmospheric gases include nitrogen (78%), oxygen(21%), nitrogen (78%), oxygen(21%), carbon dioxide, water vapor, carbon dioxide, water vapor, and argon.and argon.

• Atmosphere is changing with the Atmosphere is changing with the introduction of pollutants: increasing introduction of pollutants: increasing human energy use is increasing the human energy use is increasing the amount of carbon dioxide.amount of carbon dioxide.

• Pollutants mix with oxygen and other Pollutants mix with oxygen and other chemicals to form smog.chemicals to form smog.

Solids include dust, salt, and Solids include dust, salt, and pollen.pollen.

Liquids include water droplets Liquids include water droplets and droplets from volcanoes.and droplets from volcanoes.

Five main layers of the Five main layers of the atmosphere!!!atmosphere!!!

Lower layersLower layers

• Lowest layer, where humans live, is Lowest layer, where humans live, is the troposphere, which extends the troposphere, which extends about 10 km up, and contains most about 10 km up, and contains most of the vapor and gases.of the vapor and gases.

• Extending from 10 km to 50 km Extending from 10 km to 50 km above Earth, the Stratosphere above Earth, the Stratosphere contains ozone.contains ozone.

Upper LayersUpper Layers

• Mesosphere extends from 50 km to Mesosphere extends from 50 km to 85 km and is the layer in which 85 km and is the layer in which meteors are visible.meteors are visible.

• Thickest part of atmosphere is from Thickest part of atmosphere is from 85 km to 500km and is called the 85 km to 500km and is called the thermosphere for its high thermosphere for its high temperatures.temperatures.

Within the mesosphere and Within the mesosphere and thermosphere is a layer of thermosphere is a layer of charged particles called the charged particles called the ionosphere that can help carry ionosphere that can help carry radio waves.radio waves.

• Exosphere – outer layer of Exosphere – outer layer of atmosphere in which the space atmosphere in which the space shuttle flies, has very few molecules.shuttle flies, has very few molecules.

Atmospheric PressureAtmospheric Pressure

• PRESSURE IS GREATEST IN THE PRESSURE IS GREATEST IN THE TROPOSPHERE.TROPOSPHERE.

• PRESSURE DECREASES WITH PRESSURE DECREASES WITH ALTITUDE DUE TO FEWER PARTICLES ALTITUDE DUE TO FEWER PARTICLES OF GASES.OF GASES.

Temperature in atmospheric Temperature in atmospheric layerslayers

• The troposphere is warmed primarily The troposphere is warmed primarily by the Earth’s surface; temperature by the Earth’s surface; temperature decreases as altitude increases in this decreases as altitude increases in this layer.layer.

• Temperature increases as altitude Temperature increases as altitude increases in the stratosphere, increases in the stratosphere, particularly the upper portion because particularly the upper portion because ozone absorbs energy from the sun.ozone absorbs energy from the sun.

• Temperatures decrease with altitude in Temperatures decrease with altitude in the mesosphere.the mesosphere.

• Thermosphere and exosphere are the Thermosphere and exosphere are the first to receive the Sun’s rays so they first to receive the Sun’s rays so they are very warm.are very warm.

• SEE GRAPH PAGE 431SEE GRAPH PAGE 431

Ozone LayerOzone Layer

• about 19km to 48 km above Earth in about 19km to 48 km above Earth in the STRATOSPHERE . This layer of 3-the STRATOSPHERE . This layer of 3-atom oxygen molecules (Oatom oxygen molecules (O33) protects ) protects the Earth from the sun’s harmful the Earth from the sun’s harmful ultraviolet rays.ultraviolet rays.

• Life on Earth, as we know it, depends Life on Earth, as we know it, depends on THE OZONE LAYER!on THE OZONE LAYER!

• Pollutants called chlorofluorocarbons Pollutants called chlorofluorocarbons (CFCs) are destroying the ozone (CFCs) are destroying the ozone layer.layer.

• CFCs are used in refrigerators, air CFCs are used in refrigerators, air conditioners, aerosol sprays, and conditioners, aerosol sprays, and foam packaging.foam packaging.

• If these products develop a leak CFCs If these products develop a leak CFCs can enter the atmosphere.can enter the atmosphere.

• The ozone layer has a large hole over The ozone layer has a large hole over Antarctica.Antarctica.

Section II – Energy transfer in Section II – Energy transfer in the Atmospherethe Atmosphere• Some energy from the Sun is Some energy from the Sun is

reflected into space, some is reflected into space, some is absorbed by the atmosphere, and absorbed by the atmosphere, and some is absorbed by land and water some is absorbed by land and water on Earth’s surface.on Earth’s surface.

HeatHeat

• Energy that flows from an object or Energy that flows from an object or location with a higher temperature to location with a higher temperature to one with a lower temperature.one with a lower temperature.

#1:Radiation#1:Radiation

Energy transfer in rays or waves. Solar Energy transfer in rays or waves. Solar energy travels to earth by radiation!!energy travels to earth by radiation!!

#2:Conduction#2:Conduction• transfer of energy when molecules transfer of energy when molecules

bump into each other through bump into each other through “contact”.“contact”.

#3:Convection#3:Convection

Transfer of heat by the “flow” of Transfer of heat by the “flow” of GASES (WIND) AND LIQUID ( OCEAN GASES (WIND) AND LIQUID ( OCEAN CURRENTS).CURRENTS).

• FACTORS WHICH CAUSE WIND:FACTORS WHICH CAUSE WIND:

• ““DENSITY”- COLD AIR IS MORE DENSE THAN WARM DENSITY”- COLD AIR IS MORE DENSE THAN WARM AIR BECAUSE MOLECULES ARE CLOSER TOGETHER.AIR BECAUSE MOLECULES ARE CLOSER TOGETHER.

• ““HIGH PRESSURE” AREAS ARE AREAS OF DENSER , HIGH PRESSURE” AREAS ARE AREAS OF DENSER , COLDER AIR.COLDER AIR.

• WIND BLOWS FROM HIGH PRESSURE REGIONS TO WIND BLOWS FROM HIGH PRESSURE REGIONS TO “LOW PRESSURE” REGIONS .“LOW PRESSURE” REGIONS .

The Water CycleThe Water Cycle• water moves back and forth between water moves back and forth between

Earth’s atmosphere and surface.Earth’s atmosphere and surface.

EVAPORATION: SOLAR ENERGY EVAPORATION: SOLAR ENERGY CAUSES LIQUID TO BECOME A CAUSES LIQUID TO BECOME A VAPOR.VAPOR.

Water vapor in the atmosphere Water vapor in the atmosphere can cool and return to liquid can cool and return to liquid form through condensation. form through condensation. (CLOUDS AND PRECIPITATION)(CLOUDS AND PRECIPITATION)

Section 3 – Air MovementSection 3 – Air Movement

The Coriolis EffectThe Coriolis Effect

• rotation of the Earth causes moving rotation of the Earth causes moving air and water to move in patterns air and water to move in patterns based on latitude.based on latitude.

Global WindsGlobal Winds• wind patterns, caused by convection wind patterns, caused by convection

currents combined with the Coriolis currents combined with the Coriolis Effect, affect the world’s weatherEffect, affect the world’s weather

• Diagram and info. Page 441Diagram and info. Page 441

• Near the equator, very little wind and Near the equator, very little wind and daily rain patterns called the daily rain patterns called the doldrumsdoldrums

Surface windsSurface winds

• Between the equator and 30Between the equator and 30° ° latitude (north and south) are steady latitude (north and south) are steady “trade winds”, blowing to the west.“trade winds”, blowing to the west.

• Between 30Between 30° and 60° latitude (north ° and 60° latitude (north and south) the prevailing westerlies and south) the prevailing westerlies blow to the east, in the opposite blow to the east, in the opposite direction of the trade winds.direction of the trade winds.

Upper troposphereUpper troposphere• narrow belts of strong winds called narrow belts of strong winds called

jet streamsjet streams

• Jet streams move faster in the Jet streams move faster in the winter.winter.

• Moves storm systems across the Moves storm systems across the country.country.

Local wind systems affect local Local wind systems affect local weather.weather.• Sea Breezes – a convection current Sea Breezes – a convection current

blows wind from the cooler sea blows wind from the cooler sea toward warmer land during the day.toward warmer land during the day.

• Land Breezes – at night, air moves Land Breezes – at night, air moves off the land toward the water as the off the land toward the water as the land cools more rapidly than the land cools more rapidly than the water.water.