180 likes | 316 Views
Energy Transfer from Sun. Electromagnetic energy is a type of energy that is radiated by the sun in the form of transverse waves vibrating at right angles to the direction of movement. Radiation occurs in different forms identified by their wavelengths.
E N D
Energy Transfer from Sun Electromagnetic energy is a type of energy that is radiated by the sun in the form of transverse waves vibrating at right angles to the direction of movement
Radiation occurs in different forms identified by their wavelengths
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)
Radiation Conduction Convection Once energy is absorbed within the Earth-Atmosphere systemHEAT can be transported be 3 methods
Radiant Energy examples: 1. Sun warms face 2. Apparent heat of the fire
CONDUCTION – MOLECULES TRANSFER KINETIC ENERGY (KE) THROUGH VIBRATIONS OR COLLISIONS SOLIDS BEST FOR CONDUCTION MOLECULES CLOSE TOGETHER
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 EMITS LONGWAVE RADIATION – TERRESRIAL INFRARED RADIATION
TROPOSPHERE IS MAINLY HEATED BY RERADIATED TERRESTRIAL INFRARED RADIATION FROM EARTH “GREENHOUSE EFFECT”
GREENHOUSE GASES CARBON DIOXIDE AND METHANE THE BURNING OF FOSSIL FUELS
Life on Earth due to Greenhouse Effect • Earth is the “Goldilocks Planet” – just right – average temperature is 59° F (w/o GE our average temperature would be -3° F) • Mars’ average temperature is -67° F (1/5 of our atmosphere) • Venus’ average temperature due to GE is 855° F • Mercury’s temperature 333° F
RADIATION BALANCE DYNAMIC EQUILIBRIUM INPUT = OUTPUT Is global warming changing the balance???????
¾ OF THE ENERGY ABSORBED BY EARTH EVAPORATES WATER FROM THE OCEANS EVAPORATION 540 CALORIES/GRAM GAINED The gram of water absorbed 540 calories of latent heat as it changed to vapor (require addition of energy) COOLING EFFECT CONDENSATION 540 CALORIES/GRAM RELEASED The gram of water released 540 calories of latent heat as it changed to liquid (give off energy) WARMING EFFECT