3. Temperature

Question 1

What is temperature vs. heat energy

Answer 1

Temperature indicates level of molecular activity (no activity at 0K / -273C), Heat energy depends on volume, e.g. ver small hot mass has less heat energy than very large mass at lower temperature

Question 2

Specific Heat (Definition and examples)

Answer 2

Ratio of energy it takes (relative to 1 = water) to achieve same temperature change

Water: 1.0
Rock: 0.25 (only takes 1/4 of energy to raise temp by same amount)
Ice: 0.5

(Reason why land warms and cools much quicker than sea)

Question 3

Latent Heat

Answer 3

Energy required to change state of water (loosen the molecular bonds, no increase in temperature)

Ice to Liquid: 80cals per gram absorbed (and released in reverse)
Liquid to gas: 540 calls per gram

I.e., one gram of water vapour condensing releases 540 cals of energy

Question 4

3 ways the Troposphere is heated

Answer 4

• Radiation: Sun heats earth, earth emits longer wave length radiation (cooler) which is absorbed by water vapour, carbon dioxide and clouds
• Conduction: direct exchange of heat energy between the layer of air in touch with the surface (distributed via turbulence)
• Convection: warm air rising, carrying ordinary heat energy and latent heat energy (e.g., released when water vapour condenses to form clouds)

Question 5

What causes most heat transfer in the troposphere

Answer 5

Release of latent heat in water vapour

Question 6

Advection

Answer 6

Horizontal movement of air (wind)

Question 7

Why does cloud cover trap heat?

Answer 7

Clouds reflect back some of the low wavelength radiation from the earth