1. Warm-up
What is air made of?

2. The Atmosphere
Chapter 11

3. Layers of the Atmosphere
The atmosphere is a mixture of gases that surrounds the Earth
It provides us with the oxygen we need to breathe and protects us from the Sun’s harmful rays.
The layers differ according to temperature and composition.

4. Earth’s Atmosphere is 78% Nitrogen
21% Oxygen
1% Argon and Carbon Dioxide
Ozone (O3) exists in small quantities, absorbs ultraviolet (UV) radiation from the sun

5. Thermosphere- The upper-most layer; Temperature increases as altitude increases. Temperature can exceed one thousand degrees but it would still feel very cold km

6. Mesosphere- middle layer, coldest layer, temperature decreases as altitude increases. 50-80km

7. Stratosphere- the layer that contains the ozone layer- temperature increases as altitude increases km

8. Troposphere- lowest layer of the atmosphere; layer where we live and where all weather takes place. Temperature decreases as altitude increases km

9. Temperature and Pressure Variation in the Atmosphere

10. Heat Transfer
Heat is the energy transfer from one object to another because of a difference in temperature
Temperature is a measure of the average energy of the individual atoms/molecules in a substance
Measured in Fahrenheit (F), Celsius (C), and Kelvin (K)

11. Types of Heat Transfer

12. Radiation
Radiation: transfer of energy through electromagnetic waves

13. Solar Radiation & The Earth
3 results of solar radiation hitting the Earth:
Energy is absorbed by an object
Energy travels through an object
Energy is reflected by an object

14. Conduction Conduction: transfer of heat energy through a solid object
Blacksmith heating metal to change its shape

15. Convection
Convection: transfer of heat energy through movement of a liquid or gas
Boiling Water

16. Wind Wind- the movement of air caused by differences in air pressure
The greater the difference in pressure the faster wind moves

17. Humidity- The amount of water vapor in the air
Relative humidity- is the amount of moisture in the air compared to what the air can "hold" at that temperature. When air is holding all the water it can at a given temperature, it is said to be saturated. Measured with a psychrometer.

18. Dew Point- the temperature at which a gas condenses into a liquid
Dew Point- the temperature at which a gas condenses into a liquid. At its dew point the air is saturated. It depends on temperature and the amount of water in the air

19. Condensation Change from a gas to a liquid
Water vapor changes to form water droplets

20. Cloud Formation

21. Clouds
A cloud is a collection of millions of tiny water droplets or ice crystals.

22. Cumulus clouds:
Puffy, white clouds that tend to have flat bottoms
Indicate fair weather
When they get larger they can produce storm clouds called cumulonimbus clouds

23. Stratus clouds:
Clouds that form in layers
Cover large areas
Nimbostratus clouds are dark stratus clouds that produce light to heavy continuous rain

24. Cirrus Clouds:
Thin, feathery, white clouds
Found at high altitude
When they get thicker, it indicates a change in weather.

25. Alto- describes clouds at middle altitudes
Cirro- describes clouds that form at high altitudes
Nimbo- likely to produce precipitation
Fog- a stratus cloud that formed close to the ground