do now for wednesday, october 10th which is cooler on a hot, sunny day, a parking lot or a field of...

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Do Now for Wednesday, October 10th

Which is cooler on a hot, sunny day, a parking lot or a field of grass? EXPLAIN WHY!!!

Do Now for 10 – 11 – 12!

• It’s the middle of winter and the heat has stopped working in your house. DISCUSS three ways you could stay warm in this situation.

“Do Now” for Monday, Oct. 15

• Hypothesize: Which would heat up faster on a warm sunny day, the water in a lake or the sandy beach around it?

• Which will cool off faster after the sun goes down?

Do Now for Tuesday, October 16• Mr. Van Etten has three machines he is using

to make popcorn. Use science terms from chapter 16 to describe what types of heat is each one producing in the process of making this treat?

Thermal (heat) EnergyWe are learning to: describe how thermal energy transfers occur in the atmosphere an ocean .

We are looking for how energy from the sun is transferred by radiation, conduction andconvection to the atmosphere and ocean.

Energy TransferWe are learning to: explain the relationship between thermal energy to the formation of both atmospheric and ocean currents.

We are looking for; explain how currents form from thermal energy transfers that occur in the atmosphere and oceans.

Week 8 – Heat Energy and Energy Transfer Ch. 16 - 1

Convection-Conduction-Radiation

Electromagnetic waves travel through space and deliver energy to our atmosphere. Most

heat energy travels to Earth as radiation!

*

The term “RADIATION” is used to describe electromagnetic energy.

• .

In the middle of the day, the sky appears blue due to “scattered visible light.”

• Gas molecules in our atmosphere help to scatter short wavelength light so the afternoon sky looks blue or violet.

At dawn or dusk, the sky and clouds can look orange or red because the blue light spectrum is

removed at these times

Much of this infrared energy in our atmosphere is absorbed by water vapor (clouds), CO2 and other gases. This heat is held around Earth in a

“GREENHOUSE EFFECT.”

The Greenhouse Effect is a natural process that has kept temperatures suitable to support life on Earth for thousands and

millions of years!

Human impact over the past 200 years has added more and more CO2 to our atmosphere causing global temperatures to increase.

Heat travels from hotter objects to cooler objects in three ways.

• Radiation!• Heat transfer by electromagnetic waves. Examples

include the sun, a campfire, microwave oven or nuclear radiation. Similar to the sun, the Earth gives off or radiates heat. Do living things radiate heat?

Conduction!• The direct transfer of heat from one substance to

another (touching).Examples include feet on hot sand, a hand warmer, a pot on a stove, heat passing through the Earth.

Convection!

• The transfer of heat through a fluid (gas or liquid). Hot air vent (furnace blower), hair dryer, clothes dryer, “convection oven – stove,” hot air popcorn popper.

All three processes are at work in our troposphere.

• Most of the heat transfer in our troposphere as well as our oceans comes from CONVECTION.

• Closer to the ground, the air gets warmer. The warm air rises and becomes denser and then sinks back. A cycle of warming and cooling occurs.

In our oceans, CONVECTION is responsible for causing currents!

Even under ground, CONVECTION currents are at work!

The Gulf Stream is an ocean current created by convection currents!

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