Energy in the Atmosphere

Aim: How is energy transferred to heat the atmosphere?

1. Radiation

• All forms of energy from the sun that travel through space

• Travel as electromagnetic waves• Filtered by gases in the atm

• Electromagnetic waves are classified by wavelength

• Long Wavelength- low energy

• Short Wavelength- high energy

Page 14 of ESRT!

A.

-aka White Light-a mixture of all the colors seen in a rainbow-colors are due to different wavelengths

Visible Light Spectrum

Try this:

- Get colored pencils: - Red, Orange,Yellow,Green,Blue,Violet

– Use the spectroscope to look at the lights in the room and then out the window.

– Draw what you see:• Room’s light Sun’s light

When you see the color white, all of the wavelengths of color are being reflected (bounced back) off the material and into your eyes.

When you see black, all of the wavelengths of color are being absorbed (taken into) into the material…nothing is reflected into your eyes.

B.

• -longer wavelength than visible light• -felt as heat

C.

• shorter wavelength than visible light• does not produce heat• causes sunburn

Which wavelength has more energy?

2. What happens to sun’s energy?

• Referred to as INSOLATION

IN-incomingSOL-solarATION- radiation

a. Scattering• Clouds, dust and gas molecules reflect

and bend rays sending them in all directions

• Causes sky to appear blue and sunsets to appear reddish

b. Reflection

• Determined by surface color and texture– Lighter smooth surfaces reflect more

• About 30% of solar radiation is reflected into space by Earth’s surface, atm, or clouds.

• Albedo: ability of a surface to reflect light

• What colors will have a higher albedo?

Think: Why are ski goggles tinted like sunglasses?

c. absorption

• Determined by surface color and texture– Darker rough surfaces absorb more

• About 50% of solar radiation is absorbed by Earth’s surface

Which do you think will heat up faster: Water or Sand?

Which do you think will cool off faster: Water of Sand?

3. Conduction

• Molecules that are heated up move more quickly

• They come in contact with other molecules, transferring the energy

• Heat from Earth’s surface warms air molecules directly above

4. Convection• Due to uneven heating of fluids• In atm, warm air expands, becomes less

dense, and rises

-Radiation travels to Earth and is absorbed

-Objects re-radiate energy back as infrared waves

-Atm gases trap heat energy keeping lower atm warm

5. Green House Effect

It’s a GOOD thing!

a. The Earth’s greenhouse traps just enough heat to keep our planet a good temperature for life.

b. What would the Earth be like without the greenhouse effect?

If we’re not careful…It’s a BAD thing!

c. Burning of fossil fuels adds carbon dioxide to the air.

d. The more greenhouse gases in the air, the more heat will be trapped and global warming will occur.

• Explain what you may observe if you stand out in the sun for some time.

• How did the energy from the sun play a role in your experience?

Radiation

Conduction

Convection