Energy Transfer from SunEnergy Transfer from Sun

Electromagnetic energyElectromagnetic energy is a is a type of energy that is type of energy that is radiated by the sun in the radiated by the sun in the form of transverse waves form of transverse waves vibrating at right angles to vibrating at right angles to the direction of movementthe direction of movement

Radiation occurs in different forms identified by their wavelengths

The maximum intensity of insolation occurs in the range of wavelengths of visible light

INSOLATION REACHING INTERFACE BETWEEN SPACE / ATMOSPHERE IS DIFFERENT FROM THE INSOLATION REACHING EARTH’S SURFACE

WHAT HAPPENS TO ELECTROMAGNETIC ENERGY (RADIATION) ONCE IT REACHES EARTH?

Radiation is reflected – bounced back at the same angle they arrived

Radiation is scattered – reflected in various directions

Radiation is refracted - bent

Radiation is transmitted – pass through the material

Radiation is absorbed (taken in as heat energy)

Surface Properties Surface Properties light vs. dark smooth vs. roughlight vs. dark smooth vs. rough

SUN EMITS MAXIMUM INTENSITY IN THE SUN EMITS MAXIMUM INTENSITY IN THE VISIBLE LIGHT RANGEVISIBLE LIGHT RANGE

EARTH EMITS MAXIMUM INTENSITY IN THE EARTH EMITS MAXIMUM INTENSITY IN THE INFRARED RANGEINFRARED RANGE

Radiation Radiation ConductionConductionConvectionConvection

Once energy is absorbed within the Once energy is absorbed within the Earth-Atmosphere systemEarth-Atmosphere system HEAT can be transported be 3 HEAT can be transported be 3 methodsmethods

Radiant Energy examples:

1. Sun warms face

2. Apparent heat of the fire

CONDUCTION – MOLECULES TRANSFER CONDUCTION – MOLECULES TRANSFER KINETIC ENERGY (KE) THROUGH KINETIC ENERGY (KE) THROUGH VIBRATIONS OR COLLISIONSVIBRATIONS OR COLLISIONS

SOLIDS BEST FOR CONDUCTION MOLECULES CLOSE TOGETHER

CONDUCTION – HEAT TRANSFERRED BY VIBRATIONS OF ALUMINUM MOLECULES IN BAR - SOLIDSCONVECTION – HEAT TRANSFERRED BY DENSITY DIFFERENCES IN THE LIQUID – FLUIDS (LIQUIDS – ATMOSPHERE)

CONVECTION OCCURS IN THE ATMOSPHERE

CONDUCTION HEATS ONLY THE LOWEST ATMOSPHERE TOUCHING EARTH’S SURFACE (UP TO ABOUT 6 FT.) CONVECTION CAUSES AIR TO RISE DUE TO DENSITY DIFFERENCES

EARTH ABSORBS SHORTWAVE RADIATIONEARTH ABSORBS SHORTWAVE RADIATIONEARTH EMITS LONGWAVE RADIATIONEARTH EMITS LONGWAVE RADIATION – –

TERRESRIAL INFRARED RADIATIONTERRESRIAL INFRARED RADIATION

TROPOSPHERE IS MAINLY HEATED BY TROPOSPHERE IS MAINLY HEATED BY RERADIATED TERRESTRIAL INFRARED RERADIATED TERRESTRIAL INFRARED RADIATION FROM EARTH RADIATION FROM EARTH

“ “GREENHOUSE GREENHOUSE EFFECT”EFFECT”

GREENHOUSE GASESGREENHOUSE GASES

CARBON DIOXIDE AND METHANE

THE BURNING OF FOSSIL FUELS

Life on Earth due to Greenhouse Life on Earth due to Greenhouse EffectEffect

Earth is the “Goldilocks Planet” – just right – Earth is the “Goldilocks Planet” – just right – average temperature is 59average temperature is 59°° F (w/o GE our average F (w/o GE our average temperature would be -3temperature would be -3° F)° F)

Mars’ average temperature is -67° F (1/5 of our Mars’ average temperature is -67° F (1/5 of our atmosphere)atmosphere)

Venus’ average temperature due to GE is Venus’ average temperature due to GE is 855855° F ° F

Mercury’s temperature 333° F (daytime)Mercury’s temperature 333° F (daytime)Nighttime – can be -333!!Nighttime – can be -333!!

RADIATION BALANCERADIATION BALANCE

DYNAMIC EQUILIBRIUMDYNAMIC EQUILIBRIUM INPUT = OUTPUTINPUT = OUTPUT

Is global warming changing the balance???????

Water heats up more slowly mainly Water heats up more slowly mainly due to its high due to its high Specific HeatSpecific Heat (takes 5 x longer than land) (takes 5 x longer than land)

CLIMOGRAPHS: 30-YEAR AVERAGES (1971 - 2000)

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9.62 7.87 7.37 4.93 3.28 2.57 1.16 1.21 2.61 5.61 10.5 10.4

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AKRON, OHSAN DIEGO, CAABERDEEN, SD

CHARLESTON AP,SCAKRON, OH

SAN DIEGO, CAABERDEEN, SD

CHARLESTON AP,SC

By Charles Burrow s

MODERATING EFFECT OF MODERATING EFFECT OF LARGE BODIES OF WATERLARGE BODIES OF WATER

2 types of Heat Energy2 types of Heat Energy

Kinetic Energy – is energy in motion. Kinetic Energy – is energy in motion. Temperature is the average KE of Temperature is the average KE of moleculesmolecules

Potential Energy – is energy in storage Potential Energy – is energy in storage aka latent heat or hidden energy. Cannot aka latent heat or hidden energy. Cannot be measured with a thermometerbe measured with a thermometer

Change in State (Phase Change)Change in State (Phase Change)

Change in state is a change in potential Change in state is a change in potential energyenergy

Known as latent heat because it does not Known as latent heat because it does not cause a temperature changecause a temperature change

During the phase change energy can be During the phase change energy can be absorbed or released but the energy is absorbed or released but the energy is hidden because it hidden because it DOES NOT SHOW A DOES NOT SHOW A CHANGE IN TEMPERATURECHANGE IN TEMPERATURE

DURING CHANGE OF STATE, ENERGY IS CONVERTED TO POTENTIAL ENERGY OR STORED HEAT – DOES NOT SHOW A CHANGE IN TEMPERATURE

Condensation and freezing – release energy Evaporation and melting – require energy

¾ OF THE ENERGY ABSORBED BY ¾ OF THE ENERGY ABSORBED BY EARTH EVAPORATES WATER FROM EARTH EVAPORATES WATER FROM

THE OCEANSTHE OCEANSEVAPORATION EVAPORATION 540 CALORIES/GRAM GAINED540 CALORIES/GRAM GAINEDThe gram of water absorbed 540 calories of latent The gram of water absorbed 540 calories of latent heat as it changed to vapor (heat as it changed to vapor (require addition of energyrequire addition of energy)) COOLING EFFECTCOOLING EFFECT

CONDENSATIONCONDENSATION 540 CALORIES/GRAM RELEASED540 CALORIES/GRAM RELEASEDThe gram of water released 540 calories of latent The gram of water released 540 calories of latent heat as it changed to liquid (heat as it changed to liquid (give off energygive off energy)) WARMING EFFECTWARMING EFFECT