1. Atmosphere Review

2. Do Now
Put everything you do not need for science away.
Write down the question and the complete answer!
Take out your homework.
BE QUIET
I will not answer any questions that do not come with a raised hand
What kind of pressure is present when the air is cool?
A low pressure
B high pressure
C no pressure
D average pressure

3. Objective
At the end of today’s lesson, I will understand the major ideas in the atmosphere unit.

4. Layers of the Atmosphere
The atmosphere is divided into five layers based on temperature and air pressure changes.
The first layer/bottom layer is the troposphere. We live in the troposphere and all weather and life happens there.

5. Layers of the Atmosphere
The second layer is the stratosphere. The ozone layer, which protects us from harmful sun rays, is in the stratosphere. As altitude rises, the temperature rises.
The third layer is the mesosphere. The mesosphere is the coldest layer.
The fourth layer is the thermosphere. It has a very high temperature but is not very hot.
The fifth and highest layer is the exosphere. This is outer space.

7. Atmospheric Heating
The atmosphere is heated in three ways: conduction, radiation, and convection.
Conduction is heat transfer that occurs when two materials touch each other and heat energy goes from one to the other.

8. Atmospheric Heating
Radiation is the transfer of energy as electromagnetic waves. Radiation happens when you feel heat but aren’t touching a heat source.
Convection is the transfer of heat by circulation, or movement, of a liquid or gas.

9. Greenhouse Gases and Global Warming
The atmosphere is heated by the greenhouse effect. The greenhouse effect is the process by which gases in the atmosphere absorb thermal energy and radiate it back to Earth.
Global temperatures are increasing, and scientists are calling this global warming. Some scientists think that an increase of greenhouse gases such as carbon dioxide is causing global warming.

11. Wind
Wind is caused by differences in air pressure. These differences in air pressure are due to the uneven heating of earth by the sun. Less dense, warm air, which creates areas of low pressure, rises. As that warm air travels toward the poles, it cools down and sinks, which creates areas of high pressure. Cool air has high pressure and high density. The cool air then travels back towards the equator, completing the convection current.

12. Wind
The Coriolis Effect causes the winds to curve, instead of travel in a straight line. The Coriolis Effect is caused by the rotation of Earth.
There are three global winds. They are the polar easterlies, the westerlies, and the trade winds.
Sea and land breezes are caused by changes in temperature where the water meets the land. Sea breezes happen during the day and land breezes happen at night.

14. Cloud Formation
The first step is evaporation. Energy from the Sun causes water to evaporate
*Evaporation means water is turning from a liquid to a gas.
The second step is vapor movement. The evaporated water, or water vapor travels upward towards the atmosphere
The third step is condensation. When water vapor cools it turns back into a liquid. This process is known as condensation.
*Condensation is when gases (like water vapor) turn back into liquids
When condensation occurs in the upper atmosphere, clouds are formed.

16. Independent Practice
Your completed packet is worth 35 points and will count as your quiz this week. You may use all of your notes from the Atmosphere Unit.
There is no talking. Every time you talk, you will lose points from your total grade.
You have the rest of class to work on this packet.