1. WATER IN THE ATMOSPHERE Honors Earth science Chapter 16

2. Water vapor Is a gas You cannot see it!!! What state of matter are: –Clouds? –Fog?

3. Give examples of water in the atmosphere Solids- Liquids- Gas-

4. Water changes state (from worksheet) Liquid → Solid –freezing Solid → liquid –melting Gas (water vapor)→ liquid condensation Liquid → gas –evaporation

5. Water changes state Gas to solid? Deposition –Frost –Solid to gas? –Sublimation Dry ice –Most water vapor enters atmosphere through –EVAPORATION

6. WORKSHEET

7. LATENT HEAT la·tent heat- nounPHYSICS the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature. Energy (heat) that is used during a phase change

8. http://jamaica. u.arizona.edu/ ic/nats1011/le ctures/ch05/FI G05_006.JPG

9. Relative Humidity

10. Capacity of Air is dependent on temperature Warm air can hold more water vapor than cold air!!

11. relative humidity Temp.= 31ºC water vapor in air= 25 g Calculate the rh: 25/29.4=.85 x 100= 85% 85% of the air is filled with water vapor What happens at 100% RH? condensation!

12. Relative humidity use real data Air temp= Relative humidity is What is the water vapor content?

14. How do we measure water vapor content? Cool it until it can’t hold anymore moisture. This temp is DEW POINT Then use chart

15. Dew point Temperature at which 100% humidity occurs (condensation temp) Frost will form if DP is below freezing –Gas solid

16. Who cares about dew point?

17. Lawn care Sports on grass Farmers/ Gardeners Bad hair days? Tell the humidity –When air temp. is closer to dew point temp, humidity is higher

18. Today’s weather Grosse Pointe