Pg tp-class15-greenhouse effect, heat transfer

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Transcript of Pg tp-class15-greenhouse effect, heat transfer

Physical GeographyClass 15:

Variations in Heating, Heat Transfer

What would happen to Earth’s albedo if we increase urban areas?

1 2 3 4

88%

0%0%

13%

1. Increase2. Decrease3. Remain the

same4. No way of

knowing

What would happen to Earth’s albedo if ice sheets and glaciers melted?

1 2 3 4

50%

0%0%

50%1. Increase2. Decrease3. Remain the

same4. No way of

knowing

Greenhouse Effect

What would happen if we took some of the greenhouse gases out of the atmosphere?

1. Temperature will increase

2. Temperature will decrease

3. Temperature will remain the same

4. We’re not sure

What happens to temperature if we add extra greenhouse gases?

1 2 3 4 5

0% 0% 0%0%0%

1. Increase2. Decrease3. Increase first,

then decrease4. No change5. We’re not sure

what would happen

Methods of Heat Transfer

Transfer of heat between objects in contact with each other OR

Between molecules that are within one object

Conduction

Vertical movement of fluids

“Hot Air Rises” ………. And cools down

Cold air sinks…. And heats up

Convection

Horizontal movement of fluids

Advection

The heating or cooling of a fluid (liquid or gas)

WITHOUT the addition or subtraction of heat

Adiabatic Heating and Cooling

Pressure decreases with elevation.A group of rising air molecules will:

33%

33%

33% 1. Squeeze together and take up less room2. Spread apart and take up more room

3. Stay the same volume

When molecules spread out, they..

33%

33%

33% 1. Collide more with other molecules2. Collide less with other molecules3. No change in number of collisions

More collisions means….

33%

33%

33% 1. Lower temperature2. Higher temperature3. No temperature change

Expansion through decreased pressure = molecules spreading apart, slowing down, cooling off

Compression through increased pressure = molecules being pushed together, colliding more, speeding up, heating up

How does this happen?

What happened? Why?

A football goes from Oneonta to the Rocky Mountains

Enter question text...

1 2 3

0% 0%0%

1. The football stayed the same

2. The football became inflated

3. The football lost air

What happens to gas in a pressurized can as it leaves the can?

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0% 0%0%

1. The gas will cool down

2. The gas will heat up

3. The gas will stay the same temperature

Latent = “hidden” heat, used or released during phase changes

Sensible = heat that results in temperature change

Latent Heat vs. Sensible Heat

Gas – no defined volume or shape Liquid – defined volume, takes shape of

container Solid – defined volume and shape

(at constant temperature)

3 phases of matter:

Phase Changes

Which is a cooling process? (one that cools down the surroundings)

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0% 0%0%0%

1. Condensation2. Evaporation3. Deposition4. Freezing